顔写真

ナリタ フミオ
成田 史生
Fumio Narita
所属
大学院環境科学研究科 先端環境創成学専攻 資源循環プロセス学講座(複合材料設計学分野)
職名
教授
学位
  • 博士(工学)(東北大学)

  • 修士(工学)(東北大学)

経歴 3

  • 1999年4月 ~ 継続中
    東北大学

  • 1998年4月 ~ 1999年3月
    株式会社トーキン

  • 1997年4月 ~ 1998年3月
    東北大学 平成9年度日本学術振興会特別研究員

学歴 3

  • 東北大学 大学院工学研究科 材料加工学専攻

    1995年4月 ~ 1998年3月

  • 東北大学 大学院工学研究科 材料加工学専攻

    1993年4月 ~ 1995年5月

  • 東北大学 工学部

    1989年4月 ~ 1993年3月

委員歴 17

  • 日本複合材料学会 マルチファンクショナル研究会 主査

    2020年4月 ~ 継続中

  • 日本複合材料学会 代議員

    2020年4月 ~ 2022年3月

  • 日本複合材料学会 東北・北海道副支部長

    2019年4月 ~ 2021年3月

  • 日本機械学会 日本機械学会論文集/Transactions of the JSME (in Japanese), Mechanical Engineering Journal, Mechanical Engineering Letters アソシエイトエディタ

    2018年4月 ~ 2021年3月

  • The 5th JSME/ASME International Conference on Materials and Processing 2014 (ICM&P 2014) Scientific Committee

    2013年4月 ~ 2014年6月

  • 日本機械学会 2013年度(第91期)材料力学部門 部門賞担当委員会 委員

    2013年4月 ~ 2014年3月

  • 日本機械学会 2013年度(第91期) 校閲委員 委員

    2013年4月 ~ 2014年3月

  • 日本機械学会 2012年度(第90期) 校閲委員 委員

    2012年4月 ~ 2013年3月

  • 日本機械学会 2012年度(第90期)材料力学部門第9技術委員会 委員長

    2012年4月 ~ 2013年3月

  • 日本機械学会 2010年度(第88期) 校閲委員

    2010年4月 ~ 2011年3月

  • 日本機械学会 第87期(2009年4月-2010年3月) 材料力学部門 第4技術委員会(若手シンポジウム) 委員

    2009年4月 ~ 2010年3月

  • 日本機械学会 2009年度(第87期) 校閲委員

    2009年4月 ~ 2010年3月

  • 2010 M&M International Symposium for Young Researcher International Organizing committee

    2009年4月 ~ 2010年3月

  • 日本機械学会 第82期(平成16年4月~平成17年3月) 材料力学部門, 第4技術委員会(若手シンポジウム) 委員

    2004年4月 ~ 2005年3月

  • 第24回MAGDAコンファレンス in Tohoku -電磁現象及び電磁力に関するコンファレンス- 実行委員

    2015年11月 ~

  • 第26回新構造・機能制御と傾斜機能材料シンポジウム 実行委員

    2015年9月 ~

  • 日本機械学会 M&M2008特集号 英文ジャーナルJSMME 編修委員 編修委員

    2008年7月 ~

︎全件表示 ︎最初の5件までを表示

所属学協会 4

  • 日本複合材料学会

  • 傾斜機能材料研究会

  • 日本機械学会

  • 日本金属学会

研究キーワード 3

  • 知的・電子材料システム設計

  • 数値破壊力学

  • 電気熱弾性力学

研究分野 3

  • ナノテク・材料 / 構造材料、機能材料 / 構造・機能材料

  • ナノテク・材料 / 材料加工、組織制御 / 材料加工・処理

  • ものづくり技術(機械・電気電子・化学工学) / 材料力学、機械材料 / 機械材料・材料力学

受賞 5

  1. 第8回「ジャパン・レジリエンス・アワード(強靱化大賞)」「STOP感染症大賞」金賞

    2022年4月 一般社団法人レジリエンスジャパン推進協議会

  2. 防災・減災×サステナブル大賞2022防災・減災×SDGs賞 アカデミー&ジュニアアカデミー部門 グローバル賞

    2022年3月 一般社団法人減災サステナブル技術協会

  3. 第72回功績賞「力学特性部門」

    2014年3月21日 日本金属学会

  4. みやぎ産業科学振興基金 研究奨励賞

    2005年5月31日 みやぎ産業科学振興基金 知能電子デバイス設計のための圧電材料システムの電気破壊・メゾ力学特性評価

  5. 第43回原田研究奨励賞

    2003年10月31日 財団法人金属研究助成会 圧電デバイス設計のための電気破壊・変形特性評価に関する研究

論文 371

  1. Screen-printed piezoelectric composites for vibrational energy harvesting in combination with structural composite laminates for powering a sensing node 査読有り

    Boyue Chen, Yu Jia, Fumio Narita, Hiroki Kurita, Yu Shi

    Composites Part B: Engineering 273 111274-111274 2024年3月

    出版者・発行元:None

    DOI: 10.1016/j.compositesb.2024.111274  

    ISSN:1359-8368

  2. Multimode auxetic piezoelectric energy harvester for low-frequency vibration 査読有り

    Longfei He, Hiroki Kurita, Fumio Narita

    Smart Materials and Structures 33 035020 2024年2月2日

    出版者・発行元:None

    DOI: 10.1088/1361-665x/ad254f  

    ISSN:0964-1726

    eISSN:1361-665X

  3. Monitoring of Allowable Bending Stress Overload in Glass‐Fiber‐Reinforced Polymer Composites Using Magnetostrictive Fe–Co Fibers 査読有り

    Kenichi Katabira, Hiroki Kurita, Kotaro Mori, Hitoshi Tamura, Fumio Narita

    Advanced Engineering Materials 26 (4) 2300529 2024年2月1日

    出版者・発行元:None

    DOI: 10.1002/adem.202300529  

    ISSN:1438-1656

    eISSN:1527-2648

  4. Effect of carbon black addition on electromechanical performance of flexible piezoelectric composite films 査読有り

    Ziwen Zhao, Yaonan Yu, Longfei He, Zhenjin Wang, Hiroki Kurita, Fumio Narita

    Composites Part A: Applied Science and Manufacturing 180 108103-108103 2024年2月

    出版者・発行元:None

    DOI: 10.1016/j.compositesa.2024.108103  

    ISSN:1359-835X

  5. Novel process for monitoring stress in carbon fiber reinforced polymer composites using magnetostrictive wires from cryogenic to high temperatures

    Kenichi Katabira, Ryosuke Komagome, Fumio Narita

    Mechanics of Advanced Materials and Structures 31 (3) 586-594 2024年2月1日

    出版者・発行元:None

    DOI: 10.1080/15376494.2022.2116755  

    ISSN:1537-6494

    eISSN:1537-6532

  6. Local impact sensing via flexible piezoelectric composite film based on highly elastic resin 査読有り

    Ziwen Zhao, Zhenjin Wang, Longfei He, Hiroshi Yokota, Yutaka Okada, Fumio Narita

    Sensors and Actuators A: Physical 368 115089-115089 2024年2月

    出版者・発行元:None

    DOI: 10.1016/j.sna.2024.115089  

    ISSN:0924-4247

  7. Measurement of Magnetic Flux Density Changes in Mode I Interlaminar Fracture in Magnetostrictive Fiber–Embedded Glass Fiber-Reinforced Polymer Composites 招待有り 査読有り

    Tomoki Miyashita, Kenichi Katabira, Hiroki Kurita, Fumio Narita

    Journal of Composites Science 8 8 2024年

  8. Effects of Thermal Boundary Resistance on Thermal Management of Gallium-Nitride-Based Semiconductor Devices: A Review 査読有り

    Tianzhuo Zhan, Mao Xu, Zhi Cao, Chong Zheng, Hiroki Kurita, Fumio Narita, Yen-Ju Wu, Yibin Xu, Haidong Wang, Mengjie Song, Wei Wang, Yanguang Zhou, Xuqing Liu, Yu Shi, Yu Jia, Sujun Guan, Tatsuro Hanajiri, Toru Maekawa, Akitoshi Okino, Takanobu Watanabe

    Micromachines 14 (11) 2076-2076 2023年11月8日

    出版者・発行元:None

    DOI: 10.3390/mi14112076  

    eISSN:2072-666X

  9. Reproducibility and Compressive Strength Enhancement of Printed Silk Fibroin–Polyethylene Glycidyl Methacrylate Composite Hydrogels Via Cellulose Nanofibers 査読有り

    L. Rova, M. Saito, H. Kurita, T. Kanno, A. Gallet-Pandellé, F. Narita

    Strength of Materials 55 (6) 1201-1208 2023年11月1日

    出版者・発行元:None

    DOI: 10.1007/s11223-024-00610-2  

    ISSN:0039-2316

    eISSN:1573-9325

  10. Quantification of damage expansion influence on frequency response function of plate for structural health monitoring with integral differential method 査読有り

    Tao Wen, Fumio Narita, Hiroki Kurita, Yu Jia, Yu Shi

    Composites Science and Technology 244 110298-110298 2023年11月

    出版者・発行元:None

    DOI: 10.1016/j.compscitech.2023.110298  

    ISSN:0266-3538

  11. Fabrication of negative magnetostrictive Japanese traditional paper (washi) with cobalt ferrite particles 査読有り

    Hiroki Kurita, Lovisa Rova, Takumi Keino, Fumio Narita

    Journal of Applied Physics 134 165001 2023年10月

    DOI: 10.1063/5.0159421  

  12. Carbon Fiber-Reinforced Piezoelectric Nanocomposites: Design, Fabrication and Evaluation for Damage Detection and Energy Harvesting 査読有り

    Yaonan Yu, Yu Shi, Hiroki Kurita, Yu Jia, Zhenjin Wang, Fumio Narita

    Composites Part A: Applied Science and Manufacturing 172 107587-107587 2023年9月

    出版者・発行元:None

    DOI: 10.1016/j.compositesa.2023.107587  

    ISSN:1359-835X

  13. Magnetostrictive Composite Bolt Fastening Characteristics and Internal Axial Force 査読有り

    Kotaro Mori, Fumio Narita, Norihito Iriya

    Advanced Engineering Materials 25 (21) 2023年8月30日

    出版者・発行元:None

    DOI: 10.1002/adem.202300771  

    ISSN:1438-1656

    eISSN:1527-2648

  14. Energy harvesting and wireless communication by carbon fiber-reinforced polymer-enhanced piezoelectric nanocomposites 査読有り

    Y. Yu, C. Luo, H. Chiba, Y. Shi, F. Narita

    Nano Energy 113 108588 2023年8月

  15. Energy-harvesting and mass sensor performances of magnetostrictive cobalt ferrite-spattered Fe–Co alloy plate 査読有り

    Hiroki Kurita, Siti Masturah, binti Fakhruddin, Kumi Y. Inoue, Takeru Nakaki, Shotaro Kuroda, Zhenjin Wang, Wakako Araki, Hitoshi Shiku, Fumio Narita

    Journal of Alloys and Compounds 951 169844-169844 2023年8月

    出版者・発行元:None

    DOI: 10.1016/j.jallcom.2023.169844  

    ISSN:0925-8388

  16. Performance Evaluation of Magnetostrictive Small Wind Turbines Using Fe–Co Alloy–Based Clad Sheets 査読有り

    Toshiki Ueno, Takeru Nakaki, Taisei Mukogawa, Shuonan Dong, Hiroki Kurita, Keisuke Otsuka, Kanjuro Makihara, Fumio Narita

    Advanced Engineering Materials 25 (19) 2300185-2300185 2023年7月12日

    出版者・発行元:None

    DOI: 10.1002/adem.202300185  

    ISSN:1438-1656

    eISSN:1527-2648

  17. Crack self-sensing capability of glass fiber reinforced polymer composites embedded with magnetostrictive fibers in mixed-mode bending 査読有り

    Tomoki Miyashita, Kenichi Katabira, Hiroki Kurita, Takeru Nakaki, Fumio Narita

    Composites Science and Technology 241 110107-110107 2023年6月

    出版者・発行元:None

    DOI: 10.1016/j.compscitech.2023.110107  

    ISSN:0266-3538

  18. Energy harvesting using a magnetostrictive transducer based on switching control 査読有り

    An Li, Keiju Goto, Yuusuke Kobayashi, Yushin Hara, Yu Jia, Yu Shi, Constantinos Soutis, Hiroki Kurita, Fumio Narita, Keisuke Otsuka, Kanjuro Makihara

    Sensors and Actuators A: Physical 355 114303-114303 2023年6月

    出版者・発行元:None

    DOI: 10.1016/j.sna.2023.114303  

    ISSN:0924-4247

  19. Design and Finite Element Analysis of the Electromechanical Performance of Functionally Graded Composites 査読有り

    Kohei Maruyama, Zhenjin Wang, Fumio Narita

    Journal of Functionally Graded Materials 36 9-12 2023年4月

  20. Negative magnetostrictive paper formed by dispersing CoFe2O4 particles in cellulose nanofibrils 査読有り

    Takumi Keino, Lovisa Rova, Alia Gallet--Pandellé, Hiroki Kurita, Fumio Narita

    Scientific Reports 13 (1) 6144-6144 2023年4月

    DOI: 10.1038/s41598-023-31655-z  

    eISSN:2045-2322

  21. Characterization of metal-core piezoelectric fiber/aluminum composite in a large-strain region 査読有り

    Tetsuro Yanaseko, Hiroshi Sato, Fumio Narita, Hiroshi Asanuma

    Materials Today Communications 35 105942-105942 2023年4月

    出版者・発行元:None

    DOI: 10.1016/j.mtcomm.2023.105942  

    ISSN:2352-4928

  22. Variation of the Tensile Properties of Basalt-Fiber-Reinforced Polybutylene Succinate Matrix Composites during Microbial Degradation 招待有り 査読有り

    Lovisa Rova, Hiroki Kurita, Shinji Kudo, Sho Hatayama, Teruyoshi Kanno, Alia Gallet--Pandellé, Fumio Narita

    Polymers 15 (7) 1796-1796 2023年4月

    DOI: 10.3390/polym15071796  

    eISSN:2073-4360

  23. Room temperature enhancement of flexural strength in silicon carbide green body via the addition of cellulose nanofiber 査読有り

    Teruyoshi Kanno, Hiroki Kurita, Fumio Narita

    International Journal of Advanced Manufacturing Technology 125 (5-6) 2055-2064 2023年

    DOI: 10.1007/s00170-023-10805-7  

    ISSN:0268-3768

    eISSN:1433-3015

  24. Batteryless wireless magnetostrictive Fe30Co70/Ni clad plate for human coronavirus 229E detection 査読有り

    Daiki Neyama, Siti Masturah, binti Fakhruddin, Kumi Y. Inoue, Hiroki Kurita, Shion Osana, Naoto Miyamoto, Tsuyoki Tayama, Daiki Chiba, Masahito Watanabe, Hitoshi Shiku, Fumio Narita

    Sensors and Actuators A: Physical 349 114052-114052 2023年1月

    出版者・発行元:None

    DOI: 10.1016/j.sna.2022.114052  

    ISSN:0924-4247

  25. Stress monitoring capability of magnetostrictive Fe–Co fiber/glass fiber reinforced polymer composites under four-point bending 査読有り

    Kenichi Katabira, Tomoki Miyashita, Fumio Narita

    Scientific Reports 12 (1) 22421-22421 2022年12月27日

    出版者・発行元:None

    DOI: 10.1038/s41598-022-25792-0  

    eISSN:2045-2322

  26. Self‐Powered Wearable Piezoelectric Monitoring of Human Motion and Physiological Signals for the Postpandemic Era: A Review 査読有り

    Yinli Wang, Yaonan Yu, Xueyong Wei, Fumio Narita

    Advanced Materials Technologies 7 (12) 2200318-2200318 2022年12月

    出版者・発行元:None

    DOI: 10.1002/admt.202200318  

    ISSN:2365-709X

    eISSN:2365-709X

  27. Mode-I fracture control of unidirectional laminated composites using MFC actuators 査読有り

    Vikas Kaushik, Nagappa Siddgonde, Fumio Narita, Anup Ghosh

    Journal of Intelligent Material Systems and Structures 33 (19) 2440-2453 2022年11月

    出版者・発行元:None

    DOI: 10.1177/1045389x221088032  

    ISSN:1045-389X

    eISSN:1530-8138

  28. Impact energy harvesting and storage through duct airflow using magnetostrictive clad films 査読有り

    Toshiki Ueno, Hiroki Kurita, Fumio Narita

    12 (11) 115109-115109 2022年11月1日

    出版者・発行元:None

    DOI: 10.1063/5.0109387  

    eISSN:2158-3226

  29. Young’s modulus and ferroelectric property of BaTiO<sub>3</sub> films formed by aerosol deposition in consideration of residual stress and film thickness 招待有り 査読有り

    Kohei Maruyama, Yoshihiro Kawakami, Fumio Narita

    Japanese Journal of Applied Physics 61 (SN) SN1011-SN1011 2022年11月1日

    出版者・発行元:None

    DOI: 10.35848/1347-4065/ac7d96  

    ISSN:0021-4922

    eISSN:1347-4065

  30. Detection of virus-like particles using magnetostrictive vibration energy harvesting 査読有り

    Hiroki Kurita, Siti Masturah, Binti Fakhruddin, Daiki Neyama, Kumi Y. Inoue, Tsuyoki Tayama, Daiki Chiba, Masahito Watanabe, Hitoshi Shiku, Fumio Narita

    Sensors and Actuators A: Physical 345 113814-113814 2022年10月

    出版者・発行元:None

    DOI: 10.1016/j.sna.2022.113814  

    ISSN:0924-4247

  31. Magnetic properties of Fe–Si–B thin films and their application as stress sensors 査読有り

    Gildas Diguet, Kei Makabe, Joerg Froemel, Hiroki Kurita, Fumio Narita, Masanori Muroyama

    Thin Solid Films 758 139428-139428 2022年9月

    出版者・発行元:None

    DOI: 10.1016/j.tsf.2022.139428  

    ISSN:0040-6090

  32. Characteristics of carbon fiber reinforced polymers embedded with magnetostrictive Fe–Co wires at room and high temperatures 査読有り

    Ryosuke Komagome, Kenichi Katabira, Hiroki Kurita, Fumio Narita

    Composites Science and Technology 228 109644-109644 2022年9月

    出版者・発行元:None

    DOI: 10.1016/j.compscitech.2022.109644  

    ISSN:0266-3538

  33. Magneto Elasticity Modeling for Stress Sensors

    Gildas Diguet, Joerg Froemel, Hiroki Kurita, Fumio Narita, Kei Makabe, Koichi Ohtaka

    Magnetism 2 (3) 288-305 2022年8月23日

    出版者・発行元:MDPI AG

    DOI: 10.3390/magnetism2030021  

    eISSN:2673-8724

    詳細を見る 詳細を閉じる

    In this article, the stress/stress sensing capability of FeSiB thin films is demonstrated and discussed. The sensing relies on the change in permeability by the application of stress, compressive and tensile, and the application of DC magnetic field. This susceptibility/permeability was tested by the exciting field (AC) being in the same direction with the applied stress. The susceptibility was shown to exhibit a maximal value at a given applied stress, the critical stress. Moreover, this maximal amplitude and position was changing with the application of an external DC magnetic field. For the DC field applied in the direction of the exciting field (AC) and longitudinal to the stress, the critical stress was shifted toward negative values and for the DC field applied perpendicularly, the critical stress was shifted toward larger positive values. This was experimentally demonstrated, and a model was constructed for a better understanding.

  34. Thermal stress control of the polymorphic transformation in MnTe semiconductor films

    Shunsuke Mori, Yinli Wang, Daisuke Ando, Fumio Narita, Yuji Sutou

    Materialia 24 101493-101493 2022年8月

    出版者・発行元:Elsevier BV

    DOI: 10.1016/j.mtla.2022.101493  

    ISSN:2589-1529

  35. Stress sensor performance of sputtered Fe-Si-B alloy thin coating under tensile and bending loads

    Hiroki Kurita, Gildas Diguet, Joerg Froemel, Fumio Narita

    Sensors and Actuators A: Physical 343 113652-113652 2022年8月

    出版者・発行元:None

    DOI: 10.1016/j.sna.2022.113652  

    ISSN:0924-4247

  36. Multifunctional cellular sandwich structures with optimised core topologies for improved mechanical properties and energy harvesting performance

    Boyue Chen, Yu Jia, Fumio Narita, Congsi Wang, Yu Shi

    Composites Part B: Engineering 238 109899-109899 2022年6月

    出版者・発行元:None

    DOI: 10.1016/j.compositesb.2022.109899  

    ISSN:1359-8368

  37. Additive manufacturing and energy-harvesting performance of honeycomb-structured magnetostrictive Fe52–Co48 alloys 査読有り

    Hiroki Kurita, Paul Lohmuller, Pascal Laheurte, Kenya Nakajima, Fumio Narita

    Additive Manufacturing 54 102741-102741 2022年6月

    出版者・発行元:None

    DOI: 10.1016/j.addma.2022.102741  

    ISSN:2214-8604

    eISSN:2214-8604

  38. Correction to: Effect of Silk Fibroin Concentration on the Properties of Polyethylene Glycol Dimethacrylates for Digital Light Processing Printing (Advanced Engineering Materials, (2021), 23, 9, (2100487), 10.1002/adem.202100487)

    Satoshi Egawa, Hiroki Kurita, Teruyoshi Kanno, Fumio Narita

    Advanced Engineering Materials 24 (5) 2022年5月

    DOI: 10.1002/adem.202200495  

    ISSN:1438-1656

    eISSN:1527-2648

    詳細を見る 詳細を閉じる

    First published: 29 June 2021 The article from this Special Issue was previously published in Advanced Engineering Materials Volume 23, Issue 9, 2021 by mistake, it should be part of the current one. For completeness we are including the title page of the article in the following page, showing the original publication details. The full text of this article can be read at: https://onlinelibrary.wiley.com/doi/10.1002/adem.202100487 (Figure presented.).

  39. Design and Optimization of a Multimode Low-Frequency Piezoelectric Energy Harvester 査読有り

    Longfei He, Fumio Narita

    International Journal of Applied Mechanics 14 (04) 2250033-1-2250033-15 2022年5月

    出版者・発行元:None

    DOI: 10.1142/s1758825122500338  

    ISSN:1758-8251

    eISSN:1758-826X

  40. Thermoelectromechanical Characteristics of Piezoelectric Composites Under Mechanical and Thermal Loading 査読有り

    Kotaro Mori, Fumio Narita, Zhenjin Wang, Tadashi Horibe, Kensuke Maejima

    Advanced Engineering Materials 24 (5) 2101212-2101212 2022年5月

    出版者・発行元:Wiley

    DOI: 10.1002/adem.202101212  

    ISSN:1438-1656

    eISSN:1527-2648

  41. Effects of Heat Treatment and Cr Content on the Microstructures, Magnetostriction, and Energy Harvesting Performance of Cr‐Doped Fe–Co Alloys 査読有り

    Kenya Nakajima, Shota Tanaka, Kotaro Mori, Hiroki Kurita, Fumio Narita

    Advanced Engineering Materials 24 (5) 2101036-2101036 2022年5月

    出版者・発行元:Wiley

    DOI: 10.1002/adem.202101036  

    ISSN:1438-1656

    eISSN:1527-2648

    詳細を見る 詳細を閉じる

    The magnetostrictive effect is one of the most useful properties of ferromagnetic materials. Vibrations in dynamic structures and machines represent a nontraditional alternative energy source, and ferromagnetic materials could potentially convert the kinetic energy of these vibrations into electrical energy using the inverse magnetostrictive effect. Herein, Fe–Co–Cr alloys are fabricated and these materials are applied to vibrational energy harvesting. Specifically, (Formula presented.) (x = 0, 0.5, 1.0, or 3.0 at%) alloys are made by arc melting in an argon atmosphere and then heat treated at temperatures that promoted magnetostrictive characteristics. The structural properties of these materials are subsequently investigated using energy-dispersive X-ray spectroscopy, while their magnetic properties are assessed with a vibrating sample magnetometer (VSM) and their magnetostrictive characteristics are evaluated with a strain gauge method. Vibrational energy harvesting experiments are conducted and the relationship between the output power and the magnetic/magnetostrictive characteristics of these alloys is examined. The data shows that magnetic permeability is an important factor determining the output power of these Fe–Co alloys, in addition to their magnetostrictive properties. The results provide a basis for the systematic development of magnetostrictive material variants and for new alloys required to meet the needs of future designs.

  42. k‐Means Clustering for Prediction of Tensile Properties in Carbon Fiber‐Reinforced Polymer Composites 査読有り

    Hiroki Kurita, Masanori Suganuma, Yinli Wang, Fumio Narita

    Advanced Engineering Materials 24 (5) 2101072-2101072 2022年5月

    出版者・発行元:Wiley

    DOI: 10.1002/adem.202101072  

    ISSN:1438-1656

    eISSN:1527-2648

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    The application of computer algorithms to identify patterns in data is referred to as machine learning. The algorithms are used to learn complex relationships and build models for various predictions. Herein, the k-means method is used, one of the unsupervised learning methods in machine learning, to predict Young's modulus and ultimate tensile strength (UTS) of carbon-fiber-reinforced polymers (CFRPs), and their experimental Young's modulus and UTS values are compared. The k-means method categorizes CFRP into four colors: carbon fiber, epoxy resin matrix, defects, and contamination. The prediction of Young's modulus and UTS of CFRP with different porosities and carbon fiber orientation demonstrates the effectiveness of the k-means method. Furthermore, the experimental values of Young's modulus and UTS of commercial CFRP plate are closer to the predicted values than the catalog values. These results suggest that the k-means method can predict Young's modulus and UTS of CFRP accurately, instantly, and automatically. The k-means method is promising as a new technique to accurately and instantly understand the mechanical and physical properties of CFRPs without any material test.

  43. Inverse magnetostrictive properties of twisted Fe–Co alloy wire

    Hiroki Kurita, Zhenjin WANG, Fumio Narita

    2022年4月13日

    DOI: 10.51094/jxiv.47  

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    In this study, the inverse magnetostrictive properties of twisted Fe–Co alloy wires and the twisted Fe–Co alloy wire integrated epoxy resin matrix composites were evaluated using free and forced vibration and compressive tests. The inverse magnetostrictive properties of the twisted Fe–Co alloy wires were higher than those of the untwisted wires, with the highest values obtained for the 8-times-twisted Fe–Co alloy wires. However, no clear relationship was observed between the output voltage values and the number of twists. These findings suggested that twisting the Fe–Co alloy wire resulted in residual stress, which may have improved the inverse magnetostrictive properties.

  44. Application of deep neural network learning in composites design 招待有り 査読有り

    Yinli Wang, Constantinos Soutis, Daisuke Ando, Yuji Sutou, Fumio Narita

    2 (1) 118-171 2022年4月8日

    出版者・発行元:None

    DOI: 10.1080/26889277.2022.2053302  

    eISSN:2688-9277

  45. Direct and inverse magnetostrictive properties of Fe–Co–V alloy particle-dispersed polyurethane matrix soft composite sheets

    Hiroki Kurita, Takumi Keino, Takahiro Senzaki, Fumio Narita

    Sensors and Actuators A: Physical 337 113427-113427 2022年4月

    出版者・発行元:Elsevier BV

    DOI: 10.1016/j.sna.2022.113427  

    ISSN:0924-4247

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    Wearable and flexible magnetostrictive materials are required for the realization of devices related to the Internet of Things. Soft magnetostrictive materials are also expected to be used as tactile devices in telemedicine applications. This study reports on the successful fabrication of a material made up of Fe49Co49V2 alloy particles dispersed in a polyurethane (PU) matrix (PU–FeCoV); this material was used to make soft magnetic composite sheets with a positive magnetostriction effect. It was found that several PU–FeCoV soft composite sheets also showed a negative magnetostriction on one side of the composite sheets. This study revealed that the large pores induce this bending phenomenon in the PU–FeCoV soft composite sheet. The magnetic flux density of the PU–FeCoV soft composite sheets was found to vary with repeated loading. Hence, we believe that PU–FeCoV soft composite sheets may have potential applications as flexible sensing and vibration energy harvesting devices as well as in haptics devices.

  46. Electromechanical characterization and kinetic energy harvesting of piezoelectric nanocomposites reinforced with glass fibers 査読有り

    Kohei Maruyama, Yoshihiro Kawakami, Kotaro Mori, Hiroki Kurita, Yu Shi, Yu Jia, Fumio Narita

    Composites Science and Technology 223 109408-109408 2022年3月

    出版者・発行元:None

    DOI: 10.1016/j.compscitech.2022.109408  

    ISSN:0266-3538

  47. A novel manufacturing method and structural design of functionally graded piezoelectric composites for energy-harvesting 査読有り

    Zhenjin Wang, Kohei Maruyama, Fumio Narita

    Materials & Design 214 110371-110371 2022年2月

    出版者・発行元:None

    DOI: 10.1016/j.matdes.2021.110371  

    ISSN:0264-1275

  48. Progress on Materials Reinforcement using Mechanically Defibrillated Cellulose Nanofibers

    Hiroki Kurita, Teruyoshi Kanno, Fumio Narita

    Zairyo/Journal of the Society of Materials Science, Japan 71 (5) 417-423 2022年

    DOI: 10.2472/jsms.71.417  

    ISSN:0514-5163

    eISSN:1880-7488

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    Cellulose nanofibers (CNFs) are highly crystalline, fibrous materials with a high aspect ratio of long cellulose molecules linked together with strong hydrogen bonds. These long cellulose molecules are incorporated into hemicellulose and lignin, the cell walls of higher plants. The modulus of elasticity of CNF remains constant between -200 °C and +200 °C. However, the linear coefficient of thermal expansion of cellulose fibers was 0.17 ppm/K, which is comparable to that of quartz glass. Further, CNFs have a thermal conductivity in the same order of magnitude as glass. Therefore, they are promising next-generation fiber owing to the excellent mechanical and thermal properties, sustainability, and biodegradability of CNF. Most studies on using CNFs to increase strength have focused on polymer matrix composites, particularly biodegradable polymers. However, it is difficult to increase the strength of materials using CNFs due to the agglomeration of CNFs. Compared to other composite materials, the uniform dispersion of nanosized CNFs is crucial. This article reports that CNFs may behave not as reinforcing fibers but as cross-linking agents to strengthen the polymer when the amount of CNFs is very small in polymer matrix composites, and the addition of CNFs is also effective in strengthening silk yarn and Ti. The mechanical properties of the ceramic green bodies can be increased using CNFs as an auxiliary agent in ceramic slurry. Moreover, the fabrication of composite materials using CNFs is essential for expanding the CNFs applications.

  49. Additive Manufacturing of Magnetostrictive Fe–Co Alloys 査読有り

    K. Nakajima, M. Leparoux, H. Kurita, B. Lanfant, D. Cui, M. Watanabe, T. Sato, F. Narita

    Materials 15 (3) 709 2022年1月

  50. Fabrication and electromechanical characterization of mullite ceramic fiber/thermoplastic polymer piezoelectric composites 査読有り

    Kei Takaishi, Yuki Kubota, Hiroki Kurita, Zhenjin Wang, Fumio Narita

    Journal of the American Ceramic Society 105 (1) 308-316 2022年1月

    出版者・発行元:Wiley

    DOI: 10.1111/jace.18047  

    ISSN:0002-7820

    eISSN:1551-2916

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    Various types of sensors such as piezoelectric ceramics and strain gauges are widely used to monitor the damage of automobile components, buildings, and so on. Among these sensors, piezoelectric sensors have a high-energy conversion efficiency, that is a high sensitivity. Therefore, we fabricated a mullite fiber-reinforced resin sheet with piezoelectric particles (Piezo-MFRS) and evaluated their sensor performance. Piezo-MFRS was fabricated by the hand layup method—the polyamide resin was mixed with piezoelectric particles and infused into the mullite fiber fabric. After that, the piezo-MFRS was polarized by a corona discharge. We investigated the relationship between the applied impact load or vibration load to the piezo-MFRS and the generated voltage. The piezo-MFRS induced an output voltage of 20 mV under a compressive stress of 4 MPa, and an output voltage amplitude of 2 mV due to bending vibration of amplitude 0.5 mm. Therefore, it seems that the piezo-MFRS is suitable for use as a load sensor. Furthermore, we confirmed that the tensile properties of piezo-MFRS were not reduced by the addition of piezoelectric particles. Consequently, it is likely that piezo-MFRS is a promising material for a rugged piezoelectric sensor and opens the door to monitoring large structures.

  51. Fabrication, Tensile Properties, and Photodecomposition of Basalt Fiber-Reinforced Cellulose Acetate Matrix Composites 招待有り 査読有り

    Yuxi Shen, Alia Gallet-Pandellé, Hiroki Kurita, Fumio Narita

    Polymers 13 (22) 3944 2021年11月

    DOI: 10.3390/polym13223944  

    eISSN:2073-4360

  52. Electric polarization and crystal orientation of lead zirconate titanate under mechanical stress due to embedding in a metal matrix 査読有り

    Tetsuro Yanaseko, Hiroshi Sato, Fumio Narita, Hiroshi Asanuma

    SN Applied Sciences 3 (10) 2021年10月

    出版者・発行元:Springer Science and Business Media LLC

    DOI: 10.1007/s42452-021-04797-w  

    ISSN:2523-3963

    eISSN:2523-3971

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    <title>Abstract</title>The mechanical characteristics of piezoelectric ceramic fibers can be improved by embedding the fibers in a metal matrix. The compressive stress generated during the embedding process, however, limits the polarization of piezoelectric ceramic composites. To study and determine the relationship between the mechanical and piezoelectric properties of piezoelectric ceramics, we analyzed the crystallographic orientation of piezoelectric ceramics embedded in an aluminum matrix via electron backscatter diffraction. The orientation of the crystals before and after the polarization of the piezoelectric fibers, in which residual stresses were generated during embedding, was evaluated. Furthermore, the residual stresses were reduced by heat treatment, and the resultant angle of orientation was evaluated before and after polarization. Results showed that, as the residual stresses were relieved, the orientation of the piezoelectric ceramic crystals changed to reveal increased polarization. Our analysis shows that the crystal orientation of piezoelectric ceramics is impacted by the residual compressive stress that arises from embedding the piezoelectric fiber in the aluminum matrix; it also illustrates the hindering effect of residual stress on the polarization of piezoelectric ceramics.

  53. Evaluation of Electromechanical Properties and Conversion Efficiency of Piezoelectric Nanocomposites with Carbon-Fiber-Reinforced Polymer Electrodes for Stress Sensing and Energy Harvesting

    Yaonan Yu, Fumio Narita

    Polymers 13 (18) 3184-3184 2021年9月19日

    出版者・発行元:None

    DOI: 10.3390/polym13183184  

    eISSN:2073-4360

  54. Effect of Silk Fibroin Concentration on the Properties of Polyethylene Glycol Dimethacrylates for Digital Light Processing Printing 招待有り 査読有り

    Satoshi Egawa, Hiroki Kurita, Teruyoshi Kanno, Fumio Narita

    Advanced Engineering Materials 23 (9) 2100487-2100487 2021年9月

    出版者・発行元:None

    DOI: 10.1002/adem.202100487  

    ISSN:1438-1656

    eISSN:1527-2648

  55. On the Possibility of Developing Magnetostrictive Fe-Co/Ni Clad Plate with Both Vibration Energy Harvesting and Mass Sensing Elements 招待有り 査読有り

    Kotaro Mori, Yinli Wang, Kenichi Katabira, Daiki Neyama, Ryuichi Onodera, Daiki Chiba, Masahito Watanabe, Fumio Narita

    Materials 14 (16) 4486-4486 2021年8月10日

    出版者・発行元:MDPI AG

    DOI: 10.3390/ma14164486  

    eISSN:1996-1944

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    The severe acute respiratory syndrome coronavirus (SARS-CoV-2) has spread rapidly around the world. In order to prevent the spread of infection, city blockades and immigration restrictions have been introduced in each country, but these measures have a severe serious impact on the economy. This paper examines the possibility of both harvesting vibration energy and detecting mass by using a magnetostrictive alloy. Few efforts have been made to develop new magnetostrictive biosensor materials. Therefore, we propose magnetostrictive Fe-Co/Ni clad steel vibration energy harvesters with mass detection, and we numerically and experimentally discuss the effect of the proof mass weight on the frequency shift and output voltage induced by bending vibration. The results reveal that the frequency and output voltage decrease significantly as the mass increases, indicating that the energy harvesting device is capable of mass detection. In the future, device miniaturization and the possibility of virus detection will be considered.

  56. Structural design and performance evaluation of FeCo/epoxy magnetostrictive composites 査読有り

    Zhenjun Yang, Zhenjin Wang, Kenya Nakajima, Daiki Neyama, Fumio Narita

    Composites Science and Technology 210 108840-108840 2021年7月

    出版者・発行元:Elsevier BV

    DOI: 10.1016/j.compscitech.2021.108840  

    ISSN:0266-3538

  57. Tensile Properties of Mechanically-Defibrated Cellulose Nanofiber-Reinforced Polylactic Acid Matrix Composites Fabricated by Fused Deposition Modeling 招待有り 査読有り

    H. Kurita, C. Bernard, A. Lavrovsky, F. Narita

    Transactions of Nanjing University of Aeronautics and Astronautics 38 (1) 68-74 2021年3月

  58. Nanocellulose reinforced silkworm silk fibers for application to biodegradable polymers 査読有り

    Chen Wu, Satoshi Egawa, Teruyoshi Kanno, Hiroki Kurita, Zhenjin Wang, Eiji Iida, Fumio Narita

    Materials & Design 202 109537-109537 2021年2月

    出版者・発行元:Elsevier BV

    DOI: 10.1016/j.matdes.2021.109537  

    ISSN:0264-1275

    eISSN:1873-4197

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    In addition to its use in the conventional textile industry, Bombyx Mori silk has attracted significant attention in the materials science and biomedical engineering disciplines. Recently, the possibility of drawing silk fibers with superior toughness has gained particular research interest. Cellulose nanofiber (CNF) is widely studied as a reinforcement material owing to its excellent mechanical properties combined with relatively low density and promising biocompatibility. This paper reports silkworm silk fibers dispersed with CNF that present outstanding tensile properties compared with conventional silk fibers. The silkworm diet was modified by including CNFs, and tensile tests were carried out for the drawn silk fibers. Tensile testing of the drawn silk showed improved Young's modulus and tensile strength when the diet included CNFs at 5 wt% concentration. Fourier transform infrared spectroscopy and atomic force microscopy studies were also conducted to determine the reason for the observed improvement in properties. Morphological studies revealed that the individual fibrils or fibril bundles are aligned in the longitudinal direction of the silk fibers and are uniformly dispersed. Moreover, finite element analysis was performed to estimate the volume fraction of CNF in the silkworm silk fiber. This work opens the door for development of renewable and sustainable bio-composites.

  59. Mechanical properties of mechanically-defibrated cellulose nanofiber reinforced epoxy resin matrix composites 査読有り

    Hiroki Kurita, Ryugo Ishigami, Chen Wu, Fumio Narita

    Journal of Composite Materials 55 (4) 455-464 2021年2月

    出版者・発行元:SAGE Publications

    DOI: 10.1177/0021998320967430  

    ISSN:0021-9983

    eISSN:1530-793X

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    Cellulose nanofibers (CNF) have recently attracted attention as one of the reinforcements for composite materials. However, the same as other nanofibers, CNFs can be easily agglomerated and the nano-level defibration is necessary to obtain their outstanding properties in polymer matrices. To overcome this issue, two major defibration methods, chemical and mechanical defibration have been considered. The chemically-defibrated CNF is expensive and so prevents the practical realization of CNF as general-purpose products. Therefore, the mechanical defibration method by a clean low-cost water jet was focused on. Mechanically-defibrated CNF reinforced epoxy resin matrix (Epoxy-CNF) composite was fabricated via mechanical mixing and the variation of their tensile and flexural properties with different CNF volume fractions was evaluated. The tensile and flexural moduli of the epoxy resin were increased by CNF addition, while the fracture elongation was decreased. The calculated ultimate tensile strength (UTS) and ultimate flexural strength (UFS) of the Epoxy-CNF composites, using the aspect ratio of the agglomerated CNF clusters, indicated the validity of the random dispersion model considering the agglomerated CNF as one whole fiber. It seems that epoxy resin is enhanced by the mechanical interaction when the CNF volume fraction is higher than 0.37 vol.%.

  60. Design and Finite Element Simulation of Metal-Core Piezoelectric Fiber/Epoxy Matrix Composites for Virus Detection 査読有り

    Y. Wang, Y. Shi, F. Narita

    Sensors and Actuators A 2021年

  61. A Review of Piezoelectric and Magnetostrictive Biosensor Materials for Detection of Covid-19 and Other Viruses 査読有り

    Fumio Narita, Zhenjin Wang, Hiroki Kurita, Zhen Li, Yu Shi, Yu Jia, Constantinos Soutis

    Advanced Materials 33 (1) 2005448-2005448 2021年1月

    出版者・発行元:None

    DOI: 10.1002/adma.202005448  

    ISSN:0935-9648

    eISSN:1521-4095

  62. Electromechanical Response and Residual Thermal Stress of Metal-Core Piezoelectric Fiber /Al Matrix Composites 国際誌 査読有り

    Yinli Wang, Tetsuro Yanaseko, Hiroki Kurita, Hiroshi Sato, Hiroshi Asanuma, Fumio Narita

    Sensors 20 (20) 5799-5799 2020年10月13日

    出版者・発行元:MDPI AG

    DOI: 10.3390/s20205799  

    eISSN:1424-8220

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    It is well known that the curing residual stress induced during a fabrication process has a great influence on the performance of piezoelectric composite devices. The purpose of this work was to evaluate the residual thermal stress of lead zirconate titanate piezoelectric fiber aluminum (Al) matrix (piezoelectric fiber/Al) composites generated during fabrication numerically and experimentally and to understand the effect of the residual thermal stress on the electromechanical response. The three-dimensional finite element method was employed, and the residual stress generated during the solidification process of the Al matrix was calculated. The output voltage was also calculated in the analysis when putting stresses on the composite materials in the length direction of the piezoelectric fiber. It was shown that the cooling from higher temperatures increases the electromechanical conversion capability. Furthermore, we also performed the simulation, and we recorded the output voltage under concentrated load to investigate its application as a load position detection sensor, and we also discussed the influence of the position by changing the modeling with a different fiber position in the Al. The residual stress of hot press molded piezoelectric fiber/Al composite was then measured, and the comparison was made with the calculated values. The simulation results revealed that our model predictions reproduced and explained the experimental observations of curing residual stress. After this study, similar models of composite materials can be analyzed by this simulation, and the result can be used to design piezoelectric composite materials.

  63. Microstructure‐Enhanced Inverse Magnetostrictive Effect in Fe–Co Alloy Wires 査読有り

    Takahiro Yamazaki, Kenichi Katabira, Fumio Narita, Yasubumi Furuya, Wataru Nakao

    Advanced Engineering Materials 22 (10) 2000026-2000026 2020年10月

    出版者・発行元:Wiley

    DOI: 10.1002/adem.202000026  

    ISSN:1438-1656

    eISSN:1527-2648

  64. Potassium sodium niobate lead-free piezoelectric nanocomposite generators based on carbon-fiber-reinforced polymer electrodes for energy-harvesting structures 査読有り

    Zhenjin Wang, Hiroki Kurita, Hiroaki Nagaoka, Fumio Narita

    Composites Science and Technology 199 108331-108331 2020年10月

    出版者・発行元:Elsevier BV

    DOI: 10.1016/j.compscitech.2020.108331  

    ISSN:0266-3538

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    The ability to harvest energy from the aircraft body movement like vibration will rapidly advance the Internet of Things (IoT) for aerospace by supporting power to the IoT sensors. However, the design and development of carbon-fiber-reinforced polymer (CFRP) composites with a function such as piezoelectricity are difficult due to the conductivity of carbon. In this study, we prepare a lead-free piezoelectric nano-particle-dispersed epoxy resin with laminated CFRP prepregs in the upper and lower surfaces. A large electric field was applied by corona discharge which polarized the composite successfully. The output power of this piezo-resin/CFRP composite due to impact load was then measured. The resonant frequency and output power of the composite excited by bending vibration were also evaluated. In this study, approximately 0.8 μW/cm3 of power was generated by the impact tests and approximately 4 nW/cm3 of power was obtained by the bending vibration tests. The results suggest that the CFRP prepreg can be used as an electrode to develop CFRP composite materials with energy-harvesting performance. Such novel findings are promising for the fabrication of piezo-resin/CFRP composite generators, opening the door for the design and development of lightweight, robust, and efficient energy-harvesting structures.

  65. Twisting and Reverse Magnetic Field Effects on Energy Conversion of Magnetostrictive Wire Metal Matrix Composites 査読有り

    Zhenjun Yang, Zhenjin Wang, Manabu Seino, Daisuke Kumaoka, Go Murasawa, Fumio Narita

    physica status solidi (RRL) – Rapid Research Letters 14 (10) 2070039-2070039 2020年10月

    出版者・発行元:Wiley

    DOI: 10.1002/pssr.202070039  

    ISSN:1862-6254

    eISSN:1862-6270

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    © 2020 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim Lightweight metal matrix composites have attracted a great attention for their technological application in aerospace, automotive, or sporting goods, and the multifunctionality of these composites will further expand the range of applications. Herein, a kind of lightweight 1–3 magnetostrictive FeCo/AlSi composites is investigated to evaluate the effects of the specific structure design and reverse magnetic field on the energy conversion under compression. The microstructure of the FeCo/AlSi composite before compression was observed, and the results indicate that there is a large bonding interface, which has the benefits of strain/stress transfer. Compared with the FeCo/AlSi composite with straight FeCo wire, a design with twisted FeCo wire significantly enhances the output performance of the magnetostrictive FeCo/AlSi composite. Furthermore, comparison of the output voltage for the FeCo/AlSi composite in the N–S mode (forward magnetization) and N–N mode (reverse magnetization) reveals that the reverse magnetization can improve the efficiency of the energy conversion notably. In addition, the results of the output voltage in the theoretical calculation are virtually consistent with that in practical measurement.

  66. Experimental Evaluation of Tensile Properties of Epoxy Composites with Added Cellulose Nanofiber Slurry 査読有り

    H. Kurita, R. Ishigami, C. Wu, F. Narita

    Strength of Materials 52 (5) 798-804 2020年9月

    DOI: 10.1007/s11223-020-00233-3  

    ISSN:0039-2316

    eISSN:1573-9325

  67. Numerical and Experimental Investigation of the Through-Thickness Strength Properties of Woven Glass Fiber Reinforced Polymer Composite Laminates under Combined Tensile and Shear Loading 査読有り

    Teruyoshi Kanno, Hiroki Kurita, Masashi Suzuki, Hitoshi Tamura, Fumio Narita

    Journal of Composites Science 4 (3) 112-112 2020年8月11日

    出版者・発行元:MDPI AG

    DOI: 10.3390/jcs4030112  

    eISSN:2504-477X

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    The purpose of this paper is to investigate the through-thickness stresses of woven glass fiber reinforced polymer (GFRP) composite laminates under combined tensile and shear loading. Tensile tests were carried out with cross specimens at room temperature under various stacking angles, and the through-thickness strength properties of the woven GFRP laminates were evaluated. The failure characteristics of the woven GFRP laminates were also studied by optical microscopy observations. A three-dimensional finite element analysis (FEA) was carried out to calculate the stress distributions in the cross specimens, and the failure conditions of the specimens were examined. The numerically determined interlaminar tensile and shear stresses at failure location were consistent with Hoffman and Mohr-Coulomb failure criteria when the stacking angle was relatively small. This work is the first attempt to quantify the relation between interlaminar tensile and shear strengths of GFRP composite laminates under tensile and shear loading simultaneously using a combined numerical and experimental approach. A method based on finite element stress analysis was developed for estimating the through-thickness strength of the composite laminates using the experimentally determined fracture load and location. The results suggest that the through-thickness strength under combined tensile and shear loading can be determined effectively by this approach for relatively small stacking angles.

  68. Fabrication and Mechanical Properties of Carbon-fiber-reinforced Polymer Composites with Lead-free Piezoelectric Nanoparticles 招待有り 査読有り

    Hiroki Kurita, Zhenjin Wang, Hiroaki Nagaoka, Fumio Narita

    Sensors and Materials 32 (7) 2453-2453 2020年7月31日

    出版者・発行元:MYU K.K.

    DOI: 10.18494/sam.2020.2820  

    ISSN:0914-4935

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    Wireless sensor networks (WSNs) are one of the key factors in realizing an Internet of Things (IoT) society. Piezoelectric materials that can convert mechanical energy into electric energy directly are highly promising as energy-harvesting materials for supplying power to wireless sensors. However, it is well known that lead zirconate titanate (PZT), which has the highest piezoelectric performance, is harmful to the environment. Moreover, the high density and brittleness of the piezoceramics hinder the fabrication of a long-life energy-harvesting device. In this study, we fabricated 0-3 structure piezoelectric composite materials consisting of lead-free piezoceramic nanoparticles, epoxy resin, and carbon-fiber-reinforced polymer (CFRP) and evaluated their mechanical properties. The maximum strain energy of the piezoelectric resin/CFRP composites was 20-40% larger than that of piezoelectric/epoxy composites. The maximum stress and flexural modulus of the lead-free piezoelectric potassium sodium niobate (KNN) nanoparticles/CFRP composite were approximately 5-10% larger than those of the barium titanate (BTO) nanoparticles/CFRP composite. Consequently, it is likely that better energy harvesting performance and mechanical properties can be obtained by using KNN nanoparticles than by using BTO nanoparticles.

  69. Impact energy harvesting by Fe-Co fiber reinforced Al-Si matrix composite 査読有り

    Manabu Seino, Lixin Jiang, Zhenjun Yang, Kenichi Katabira, Tadaaki Satake, Fumio Narita, Go Murasawa

    Materialia 10 100644-100644 2020年5月

    出版者・発行元:Elsevier BV

    DOI: 10.1016/j.mtla.2020.100644  

    ISSN:2589-1529

    eISSN:2589-1529

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    © 2020 Acta Materialia Inc. The aim of this study is to investigate energy-harvesting properties of FeCo/AlSi composites under impact loading. First, FeCo/AlSi composite is fabricated using a casting process. Second, their inverse magnetostrictive characteristic is measured under compressive loading. Third, cyclic loading tests are conducted for an energy-harvesting device that consists of a FeCo/AlSi composite specimen, two magnets, and a coil. Finally, impact loading testing is applied for energy-harvesting devices using an in-house impact-loading machine: a modified Izod impact testing machine. The zigzag interface and chemical bonding leads to transfer of stress and strain between the Fe-Co fiber and the Al-Si matrix. The present energy-harvesting device based on FeCo/AlSi composite demonstrates excellent durability for impact loading, and exhibits good impact energy-harvesting properties.

  70. Multi-Scale Analysis and Testing of Tensile Behavior in Polymers with Randomly Oriented and Agglomerated Cellulose Nanofibers 査読有り

    Fumio Narita, Yinli Wang, Hiroki Kurita, Masashi Suzuki

    Nanomaterials 10 (4) 700-700 2020年4月7日

    出版者・発行元:MDPI AG

    DOI: 10.3390/nano10040700  

    eISSN:2079-4991

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    Cellulose nanofiber (CNF) has been accepted as a valid nanofiller that can improve the mechanical properties of composite materials by mechanical and chemical methods. The purpose of this work is to numerically and experimentally evaluate the mechanical behavior of CNF-reinforced polymer composites under tensile loading. Finite element analysis (FEA) was conducted using a model for the representative volume element of CNF/epoxy composites to determine the effective Young’s modulus and the stress state within the composites. The possible random orientation of the CNFs was considered in the finite element model. Tensile tests were also conducted on the CNF/epoxy composites to identify the effect of CNFs on their tensile behavior. The numerical findings were then correlated with the test results. The present randomly oriented CNF/epoxy composite model provides a means for exploring the property interactions across different length scales.

  71. Fabrication, Modeling and Characterization of Magnetostrictive Short Fiber Composites 査読有り

    Zhenjin Wang, Kotaro Mori, Kenya Nakajima, Fumio Narita

    Materials 13 (7) 1494-1494 2020年3月25日

    出版者・発行元:MDPI AG

    DOI: 10.3390/ma13071494  

    eISSN:1996-1944

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    Magnetostrictive materials have a wide variety of applications due to their great capability as sensors and energy-harvesting devices. However, their brittleness inhibits their applications as magnetostrictive devices. Recently, we developed a continuous magnetostrictive Fe-Co-fiber-embedded epoxy matrix composite to increase the flexibility of the material. In this study, we fabricated random magnetostrictive Fe-Co short fiber/epoxy composite sheets. It was found that the discontinuous Fe-Co fiber composite sheet has the magnetostrictive properties along the orientation parallel to the length of the sheet. Finite element computations were also carried out using a coupled magneto-mechanical model, for the representative volume element (RVE) of unidirectional aligned magnetostrictive short fiber composites. A simple model of two-dimensional, randomly oriented, magnetostrictive short fiber composites was then proposed and the effective piezomagnetic coefficient was determined. It was shown that the present model is very accurate yet relatively simple to predict the piezomagnetic coefficient of magnetostrictive short fiber composites. This magnetostrictive composite sheet is expected to be used as a flexible smart material.

  72. High temperature electromechanical response of multilayer piezoelectric laminates under AC electric fields for fuel injector applications 査読有り

    Fumio Narita, Ryohei Hasegawa, Yasuhide Shindo

    International Journal of Mechanics and Materials in Design 16 (1) 207-213 2020年3月

    出版者・発行元:Springer Science and Business Media LLC

    DOI: 10.1007/s10999-019-09453-1  

    ISSN:1569-1713

    eISSN:1573-8841

  73. Assessing the Flexural Properties of Epoxy Composites with Extremely Low Addition of Cellulose Nanofiber Content 査読有り

    Yingmei Xie, Hiroki Kurita, Ryugo Ishigami, Fumio Narita

    Applied Sciences 10 (3) 1159-1159 2020年2月9日

    出版者・発行元:MDPI AG

    DOI: 10.3390/app10031159  

    eISSN:2076-3417

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    Epoxy resins are a widely used common polymer due to their excellent mechanical properties. On the other hand, cellulose nanofiber (CNF) is one of the new generation of fibers, and recent test results show that CNF reinforced polymers have high mechanical properties. It has also been reported that an extremely low CNF addition increases the mechanical properties of the matrix resin. In this study, we prepared extremely-low CNF (~1 wt.%) reinforced epoxy resin matrix (epoxy-CNF) composites, and tried to understand the strengthening mechanism of the epoxy-CNF composite through the three-point flexural test, finite element analysis (FEA), and discussion based on organic chemistry. The flexural modulus and strength were significantly increased by the extremely low CNF addition (less than 0.2 wt.%), although the theories for short-fiber-reinforced composites cannot explain the strengthening mechanism of the epoxy-CNF composite. Hence, we propose the possibility that CNF behaves as an auxiliary agent to enhance the structure of the epoxy molecule, and not as a reinforcing fiber in the epoxy resin matrix.

  74. Effects of additional elements (Cr, Mo) and heat treatment on the magnetostrictive, magnetic, and mechanical properties of Co-rich Fe-Co alloys

    Kenya Nakajima, Hiroki Kurita, Fumio Narita

    Proceedings of SPIE - The International Society for Optical Engineering 11377 2020年

    DOI: 10.1117/12.2558417  

    ISSN:0277-786X

    eISSN:1996-756X

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    Magnetostrictive materials have attracted attention as materials for energy harvesting such as vibration power generation for Internet of Things (IoT). Fe-Co alloys have been focused on since the alloys have remarkable magnetic and mechanical properties. In this work, we evaluated the effect of heat treatment on the magnetic and magnetostrictive properties of rolled Fe-Co magnetostrictive films with Cr and Mo addition as bcc stabilizing elements to clarify. It was shown that the coercivity and the residual magnetism of the annealed specimens increase with the increase of the additive element quantity. This result indicates an increase in the amount of vibration power generation due to the Villari effect.

  75. Effect of composite design parameters on the inverse magnetostrictive characteristics of hybrid carbon fiber reinforced plastic embedded with Fe-Co fibers

    Kenichi Katabira, Hiroki Kurita, Ryosuke Komagome, Fumio Narita

    Proceedings of SPIE - The International Society for Optical Engineering 11377 2020年

    DOI: 10.1117/12.2557191  

    ISSN:0277-786X

    eISSN:1996-756X

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    Carbon fiber reinforced plastic (CFRP) has been generally chosen in the areas where weight reduction is important, for instance, sports goods and aerospace. For safe operation of the system using CFRP, we have to assess the damage state and predict the remaining service life accurately, which is one of the critical issues to keep the reliability in CFRP applications. Recently, multi-functional CFRP, especially embedded with piezoelectric or magnetostrictive materials, has been explored to realize lightweight battery-free sensors for structural health monitoring (SHM). In present study, the hybrid CFRP embedded with magnetostrictive Fe-Co fibers was developed, and the effect of composite design parameters (e.g. diameter of the fibers, location of the layers, bias magnetic field) on the inverse magnetostrictive response characteristic was also investigated. Mechanical cyclic bending tests showed that the fluctuation of magnetic flux density was measured resulting from the flexural deformation of our hybrid CFRP. Moreover, the measured magnetic flux density changed drastically when the CFRP was damaged, which implies that our hybrid CFRP has damage self-sensing ability. It seems that we should experimentally and numerically design and investigate the hybrid CFRP with magnetostrictive Fe-Co fibers in order to improve the capability as sensor composite materials. Accordingly, this study must make contribution to feasibility of lightweight, buttery-free, high performance stress sensors for SHM.

  76. Fabrication of potassium sodium niobate nano-particle/polymer composites with piezoelectric stability and their application to unsteady wind energy harvesters 査読有り

    Zhenjin Wang, Fumio Narita

    Journal of Applied Physics 126 (22) 224501-224501 2019年12月14日

    出版者・発行元:AIP Publishing

    DOI: 10.1063/1.5127937  

    ISSN:0021-8979

    eISSN:1089-7550

  77. Magnetomechanical design and power generation of magnetostrictive clad plate cantilever 査読有り

    Zhenjun Yang, Ryuichi Onodera, Tsuyoki Tayama, Masahito Watanabe, Fumio Narita

    Applied Physics Letters 115 (24) 243504-243504 2019年12月9日

    出版者・発行元:AIP Publishing

    DOI: 10.1063/1.5111351  

    ISSN:0003-6951

    eISSN:1077-3118

  78. Effect of Notches on Magnetic Induction Variation for Magnetostrictive Clad Plate 招待有り 査読有り

    Zhenjun Yang, Hiroki Kurita, Hiroki Takeuchi, Kenya Nakajima, Fumio Narita

    Sensors and Materials 31 (11) 3681-3681 2019年11月22日

    出版者・発行元:MYU K.K.

    DOI: 10.18494/sam.2019.2146  

    ISSN:0914-4935

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    This study focuses on the notch effect on FeCo/Ni clad plate cantilevers. We investigated the response of the cantilevers to an external load and the energy conversion performance. The three-point bending test well demonstrated that the presence of notches can broaden the variation of magnetic induction with respect to an external load. Furthermore, this variation is proportional to the load. The maximum output voltage of the notched FeCo/Ni clad plate cantilever is 2.4 times that of the cantilever without a notch. The following vibration energy harvesting experiment also revealed that the output voltage of the former was far greater than that of the FeCo/Ni clad plate cantilever without a notch by a factor of 2. The result of finite element analysis (FEA) indicated that the improvement of the energy harvesting performance was the result of localized stress concentration around the notches in response to an external load. In addition, the FeCo/Ni clad plate cantilever showed a superposed enhancement of the energy harvesting performance compared with a single FeCo plate cantilever as a result of the different properties of the FeCo and Ni alloys.

  79. Fabrication and Characterization of Carbon Fiber Reinforced Plastics Containing Magnetostrictive Fe-Co Fibers with Damage Self-Detection Capability 招待有り 査読有り

    Kenichi Katabira, Hiroki Kurita, Yu Yoshida, Fumio Narita

    Sensors 19 (22) 4984-4984 2019年11月15日

    出版者・発行元:MDPI AG

    DOI: 10.3390/s19224984  

    ISSN:1424-8220

    eISSN:1424-8220

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    Carbon fiber reinforced plastic (CFRP) is an excellent choice in the areas where weight reduction is important and multi-functionalization of CFRP, especially by adding sensor capabilities, is a promising approach to realize lightweight battery-free devices in structural health monitoring (SHM). In this study, we fabricated hybrid CFRP with Fe-Co fibers and evaluated the inverse magnetostrictive response characteristics. It was shown that the measured magnetic flux density of the CFRP fluctuates in response to cyclic bending load. It was also revealed that our Fe-Co fiber inserted CFRP has damage self-sensing ability. In addition, it seems that the optimization of design and more experimental and numerical investigation improves the capability of the hybrid CFRP with Fe-Co fiber as sensor composite materials.

  80. Improvement Estimation Accuracy of Impact Detection Using Metal‐Core Piezoelectric Fiber/Aluminum Composites 査読有り

    Tetsuro Yanaseko, Hiroshi Sato, Fumio Narita, Isao Kuboki, Hiroshi Asanuma

    Advanced Engineering Materials 21 (11) 1900550-1900550 2019年11月

    出版者・発行元:Wiley

    DOI: 10.1002/adem.201900550  

    ISSN:1438-1656

    eISSN:1527-2648

  81. Evaluation of the inverse magnetostrictive effect in heat‐treated Fe‐Co wire/polymer composites 招待有り 査読有り

    Kenichi Katabira, Natsuko Kimura, Takahiro Yamazaki, Fumio Narita

    Material Design & Processing Communications 1 (5) e81 2019年10月

    出版者・発行元:Wiley

    DOI: 10.1002/mdp2.81  

    ISSN:2577-6576

    eISSN:2577-6576

  82. Design, fabrication and evaluation of metal-matrix lightweight magnetostrictive fiber composites 査読有り

    Zhenjun Yang, Kenya Nakajima, Lixin Jiang, Hiroki Kurita, Go Murasawa, Fumio Narita

    Materials & Design 175 107803-107803 2019年8月

    出版者・発行元:Elsevier BV

    DOI: 10.1016/j.matdes.2019.107803  

    ISSN:0264-1275

    eISSN:1873-4197

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    A class of lightweight FeCo/AlSi magnetostrictive composites was prepared in this study to explore the feasibility for 1-3 metal-matrix magnetostrictive materials for serving as sensors, actuators and energy harvesters. The FeCo fibers were inset into the AlSi metal liquid and then the composites were solidified at a protective atmosphere. The microstructural observations for these FeCo/AlSi composites illustrate the presence of the element diffusion and the disappearance of the cold-rolled preferred orientation. The refined microstructure was obtained during solidification and then further improved the magnetostrictive properties of the FeCo/AlSi composites. A zigzag interface with well transfer in stress and strain between the FeCo fiber and AlSi matrix existed through both physical and chemical bonding. There are two different experimental groups in this work. One group is aimed to evaluate the effect of the diameter of the FeCo/AlSi composite on the output voltage under compression. Another group with different numbers of the FeCo fibers is employed for analyzing the effect of the volume fraction of the FeCo fiber on the output performance. The results exhibit that a smaller diameter for the lightweight 1-3 FeCo/AlSi composite contributes to exciting a greater output voltage. Furthermore, the output voltage is proportional to the number of the FeCo fiber. An optimal resistive load of 500 Ω for this harvesting setup is obtained. Theoretical analysis through a magneto-mechanical coupling model for the FeCo/AlSi composites was conducted for accurately predicting the practical output performance.

  83. Performance boost of co-rich fe-co based alloy magnetostrictive sensors via nitrogen treatment 査読有り

    Kenya Nakajima, Hiroki Kurita, Fumio Narita

    Sensors and Actuators A: Physical 295 75-83 2019年8月

    出版者・発行元:Elsevier BV

    DOI: 10.1016/j.sna.2019.05.033  

    ISSN:0924-4247

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    The inverse magnetostrictive response (i.e. a change in magnetization due to an applied stress)of magnetostrictive materials, the Villari effect is widely applied for sensor applications. Mechanical properties are an important factor when applied for vibration energy and sensor applications. Surface-treatment methods are widely used for enhanced performance and serviceability of engineering components, and nitriding is one of the most versatile surface engineering method nowadays. These methods allow the fine tuning of surface quality-dependent properties such as the resistance to fatigue, wear, and corrosion. In this study, the change of inverse magnetostrictive characteristics of Co-rich Fe-Co bimetals by the nitriding treatment, for 30 min at 580 °C, was evaluated. The effect of the nitriding treatment on the inverse magnetostrictive characteristics, magnetostrictive susceptibility and magnetic hysteresis loop of Fe-Co bimetals, by an applied load, were evaluated by three-point bending tests under a magnetic field. Furthermore, the output voltage of the as-rolled Fe-Co/Ni bimetal and the nitrided Fe-Co/Ni bimetal cantilevers, under bending vibration, were compared. The nitride Fe-Co/Ni bimetal construct exhibited a high output voltage compared to the as-rolled Fe/Ni bimetal.

  84. Crack initiation behavior of titanium boride whisker reinforced titanium matrix composites during small punch testing 招待有り 査読有り

    Hiroki Kurita, Kazuya Sakayanagi, Shoichi Kikuchi, Noriharu Yodoshi, Sophie Gourdet, Fumio Narita

    Material Design & Processing Communications 1 (4) e80 2019年8月

    出版者・発行元:Wiley

    DOI: 10.1002/mdp2.80  

    ISSN:2577-6576

    eISSN:2577-6576

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    TiB whisker reinforced Ti matrix composites are potential aerospace materials due to their outstanding specific tensile properties. However, it is necessary to enhance their fracture toughness for their practical realization. In this study, we investigate the crack initiation behavior on the surface of TiB whisker reinforced Ti-6Al-4 V alloy matrix (Ti6Al4V-TiB) composites under tensile loading during small punch testing. It is revealed that initial cracks of the Ti6Al4V-TiB composite occur from the fracture of TiB whiskers, and these cracks are united after propagating in the β phase of the Ti-6Al-4 V alloy matrix.

  85. Strengthening Mechanism of Titanium Boride Whisker-Reinforced Ti-6Al-4V Alloy Matrix Composites with the TiB Orientation Perpendicular to the Loading Direction 招待有り 査読有り

    Hiroki Kurita, Shiori Suzuki, Shoichi Kikuchi, Noriharu Yodoshi, Sophie Gourdet, Fumio Narita

    Materials 12 (15) 2401-2401 2019年7月28日

    出版者・発行元:MDPI AG

    DOI: 10.3390/ma12152401  

    eISSN:1996-1944

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    We fabricated fully dense titanium boride (TiB) whisker-reinforced Ti-6Al-4V alloy matrix (Ti6Al4V-TiB) composites, with a homogeneous dispersion, a TiB orientation perpendicular to the loading direction (; two-dimensional random direction) and an intimate Ti/TiB interface without an intermediate interfacial layer in the Ti-6Al-4V alloy matrix, by spark plasma sintering. Microstructural analysis allows us to present the tensile properties of the Ti6Al4V-TiB composites with the theories for discontinuous fiber-reinforced composites. The Ti6Al4V-TiB 10 vol.% composite yielded a Young’s modulus of 130 GPa, an ultimate tensile strength (UTS) of 1193 MPa and an elongation of 2.8%. The obtained experimental Young’s modulus and UTS of the Ti6Al4V-TiB composites were consistent with the theoretical values estimated by the Halpin-Tsai and Shear-lag models. The good agreement between our experimental results and these models indicates that the TiB whiskers behave as discontinuous fibers in the Ti-6Al-4V alloy matrix.

  86. Corona Poling Conditions for Barium Titanate/Epoxy Composites and their Unsteady Wind Energy Harvesting Potential 査読有り

    Zhenjin Wang, Fumio Narita

    Advanced Engineering Materials 21 (7) 1900169-1900169 2019年7月

    出版者・発行元:Wiley

    DOI: 10.1002/adem.201900169  

    ISSN:1438-1656

    eISSN:1527-2648

  87. Footstep Energy Harvesting with the Magnetostrictive Fiber Integrated Shoes 招待有り 査読有り

    Hiroki Kurita, Kenichi Katabira, Yu Yoshida, Fumio Narita

    Materials 12 (13) 2055-2055 2019年6月26日

    出版者・発行元:MDPI AG

    DOI: 10.3390/ma12132055  

    eISSN:1996-1944

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    Wearable energy harvesting devices attract attention as the devices provide electrical power without inhibiting user mobility and independence. While the piezoelectric materials integrated shoes have been considered as wearable energy harvesting devices for a long time, they can lose their energy harvesting performance after being used several times due to their brittleness. In this study, we focused on Fe–Co magnetostrictive materials and fabricated Fe–Co magnetostrictive fiber integrated shoes. We revealed that Fe–Co magnetostrictive fiber integrated shoes are capable of generating 1.2 µJ from 1000 steps of usual walking by the Villari (inverse magnetostrictive) effect. It seems that the output energy is dependent on user habit on ambulation, not on their weight. From both a mechanical and functional point of view, Fe–Co magnetostrictive fiber integrated shoes demonstrated stable energy harvesting performance after being used many times. It is likely that Fe–Co magnetostrictive fiber integrated shoes are available as sustainable and wearable energy harvesting devices.

  88. The insert effect of cellulose nanofiber layer on glass fiber‐reinforced plastic laminates and their flexural properties 招待有り 査読有り

    Hiroki Kurita, Yingmei Xie, Kenichi Katabira, Risa Honda, Fumio Narita

    Material Design & Processing Communications 1 (3) e58-e58 2019年6月

    出版者・発行元:Wiley

    DOI: 10.1002/mdp2.58  

    ISSN:2577-6576

    eISSN:2577-6576

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    Cellulose nanofibers (CNFs) have the potential to adhere glass fiber-reinforced plastics (GFRPs) without a decrease in their mechanical properties. In this study, we inserted two CNF layers between GFRP laminates and evaluated their flexural properties. The insert of epoxy resin with CNF of 0.1 wt% layers, increased the flexural strength of GFRP by 125%, whereas the flexural modulus of CNF layer inserted GFRP laminates was constant (28 ± 0.67 GPa). Moreover, we evaluated the flexural properties of a single CNF layer and revealed that even an extremely slight CNF (0.04 wt%) addition drastically increased the flexural strength and fracture elongation of epoxy resin by 130% and 180%, respectively.

  89. Evaluation of Vibration Energy Harvesting Using a Magnetostrictive Iron–Cobalt/Nickelclad Plate 査読有り

    Z. Yang, H. Kurita, R. Onodera, T. Tayama, D. Chiba and F. Narita

    Smart Materials and Structures 28 (3) 034001 2019年2月

    DOI: 10.1088/1361-665X/aaf9f2  

    ISSN:0964-1726

    eISSN:1361-665X

  90. Mixed Mode Fracture Behavior of Notched Giant Magnetostrictive: Mechanical Characterization and Comparison among Failure Criteria 査読有り

    M. Peron, K. Katabira, L. M. Viespoli, F. Narita, F. Berto

    Theoretical and Applied Fracture Mechanics 99 194-204 2019年2月

  91. Fabrication and Impact Output Voltage Characteristics of Carbon Fiber Reinforced Polymer Composites with Lad-Free Piezoelectric Nano-Particles 査読有り

    F. Narita, H. Nagaoka, Z. Wang

    Materials Letters 236 487-490 2019年2月

  92. 熱物性を考慮した傾斜機能圧電複合材料の環境発電特性評価

    森 孝太郎, 前嶋 研祐, 堀辺 忠志, 西 剛志, 王 真金, 成田 史生

    M&M材料力学カンファレンス 2019 OS0229 2019年

    出版者・発行元:一般社団法人 日本機械学会

    DOI: 10.1299/jsmemm.2019.os0229  

    eISSN:2424-2845

  93. 有限要素法による白金コアPZTファイバー/アルミニウムマトリックス複合材料の出力電圧解析

    王 吟麗, 楊 鎮駿, 王 真金, 柳迫 徹郎, 佐藤 宏司, 浅沼 博, 成田 史生

    年次大会 2019 S03134P 2019年

    出版者・発行元:一般社団法人 日本機械学会

    DOI: 10.1299/jsmemecj.2019.s03134p  

    eISSN:2424-2667

  94. 鉄コバルト磁歪フィラー/エポキシ樹脂シートの開発と特性評価

    王 真金, 楊 鎮駿, 帷子 健一, 栗田 大樹, 成田 史生

    年次大会 2019 S03112 2019年

    出版者・発行元:一般社団法人 日本機械学会

    DOI: 10.1299/jsmemecj.2019.s03112  

    eISSN:2424-2667

  95. 鉛フリー圧電粒子/CFRP複合材料の作製および諸特性評価

    長岡 弘朗, 王 真金, 呉 宸, 成田 史生

    M&M材料力学カンファレンス 2019 OS0228 2019年

    出版者・発行元:一般社団法人 日本機械学会

    DOI: 10.1299/jsmemm.2019.os0228  

    eISSN:2424-2845

  96. 鉛フリー圧電粒子/CFRP複合材料の作製および出力電力特性評価

    長岡 弘朗, 王 真金, 成田 史生

    年次大会 2019 S03132P 2019年

    出版者・発行元:一般社団法人 日本機械学会

    DOI: 10.1299/jsmemecj.2019.s03132p  

    eISSN:2424-2667

  97. Enhancement of Inverse Magnetostrictive Effect through Stress Concentration for a Notch-Introduced FeCo Alloy 査読有り

    Zhenjun Yang, Hiroki Kurita, Hiroki Takeuchi, Kenichi Katabira, Fumio Narita

    Advanced Engineering Materials 21 (1) 1800811-1800811 2019年1月

    出版者・発行元:Wiley

    DOI: 10.1002/adem.201800811  

    ISSN:1438-1656

    eISSN:1527-2648

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    The authors investigate the magnetic flux leakage for a class of magnetostrictive FeCo alloys with a notch undergoing compression and impact with respect to energy harvesting. The magnetic flux leakage plays a crucial role in the practical energy transition in terms of the features for energy harvesting. Therefore, the corresponding situations are systematically studied by combining finite element analysis (FEA) with practical experiments. The FeCo alloys are categorized into three groups with different three-dimensional notch shapes, and the depths of the notches are 0, 0.5, and 1 mm, respectively. The parameters in both the simulations and practical tests are completely consistent. The results of compression test carried out with a stepwise-increasing stress from 0 to 100 MPa reveal that the variations of magnetic induced flux increase with the increasing depth of the notches. The following FEA herein provides a feasible interpretation that the stress concentration around the notch is largely responsible for the notch-induced enhancement. The findings of the impacting experiments simultaneously exhibit an analogous tendency that the output power is proportional to the depth of notch. Furthermore, the stress rate has no obvious effect on the output electricity. The maximum magnitude of the improvement for the output power increases by almost 400% comparing the specimens with notches of 0 and 1 mm. This study indicates a promising feasibility to achieve vibration-energy harvesting from various irregular components.

  98. Interlaminar Tension-Tension Fatigue of Woven Glass Fiber Reinforced Plastic Composite Laminates at Low Temperatures 査読有り

    F. Narita, C. Tanaka and M. Suzuki

    6 (1) 28-33 2018年12月22日

    出版者・発行元:None

    DOI: 10.12974/2311-8717.2018.06.4  

    eISSN:2311-8717

  99. A Review on Piezoelectric, Magnetostrictive, and Magnetoelectric Materials and Device Technologies for Energy Harvesting Applications 招待有り 査読有り

    Fumio Narita, Marina Fox

    Advanced Engineering Materials 20 (5) 1700743 2018年5月1日

    出版者・発行元:Wiley-VCH Verlag

    DOI: 10.1002/adem.201700743  

    ISSN:1527-2648 1438-1656

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    In the coming era of the internet of things (IoT), wireless sensor networks that monitor, detect, and gather data will play a crucial role in advancements in public safety, human healthcare, industrial automation, and energy management. Batteries are currently the power source of choice for operating wireless network devices due to their ease of installation however, they require periodic replacement due to capacity limitations. Within the scope of the IoT, battery maintenance of the trillion sensor nodes that may be implemented will be practically infeasible from environmental, resource, and labor cost perspectives. In considering individual self-powered sensor nodes, the idea of harvesting energy from ambient vibrations, heat, and electromagnetic waves has recently triggered noticeable research interest in the academic community. This paper gives an overview of energy harvesting materials and systems. Three main categories are presented: piezoelectric ceramics/polymers, magnetostrictive alloys, and magnetoelectric (ME) multiferroic composites. State-of-the-art harvesting materials and structures are presented with a focus on characterization, fabrication, modeling and simulation, and durability and reliability. Some perspectives and challenges for the future development of energy harvesting materials are also highlighted.

  100. Effect of Temperature on the Tensile Strength of Triaxial Woven CFRP 査読有り

    Research & Development in Material Science 5 (4) 000619 2018年4月

  101. On the Energy Harvesting Potential of Lead-Free Piezoelectric Composites from Air-Flow and Temperature Change 査読有り

    5 (4) 000607 2018年4月

  102. Fabrication of Fe–Co Magnetostrictive Fiber Reinforced Plastic Composites and Their Sensor Performance Evaluation 査読有り

    Materials 11 (3) 406 2018年3月9日

    出版者・発行元:None

    DOI: 10.3390/ma11030406  

    ISSN:1996-1944

  103. Magnetostrictive clad steel plates for high-performance vibration energy harvesting 査読有り

    Zhenjun Yang, Kenya Nakajima, Ryuichi Onodera, Tsuyoki Tayama, Daiki Chiba, Fumio Narita

    Applied Physics Letters 112 (7) 073902 2018年2月12日

    出版者・発行元:American Institute of Physics Inc.

    DOI: 10.1063/1.5016197  

    ISSN:0003-6951

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    Energy harvesting technology is becoming increasingly important with the appearance of the Internet of things. In this study, a magnetostrictive clad steel plate for harvesting vibration energy was proposed. It comprises a cold-rolled FeCo alloy and cold-rolled steel joined together by thermal diffusion bonding. The performances of the magnetostrictive FeCo clad steel plate and conventional FeCo plate cantilevers were compared under bending vibration the results indicated that the clad steel plate construct exhibits high voltage and power output compared to a single-plate construct. Finite element analysis of the cantilevers under bending provided insights into the magnetic features of a clad steel plate, which is crucial for its high performance. For comparison, the experimental results of a commercial piezoelectric bimorph cantilever were also reported. In addition, the cold-rolled FeCo and Ni alloys were joined by thermal diffusion bonding, which exhibited outstanding energy harvesting performance. The larger the plate volume, the more the energy generated. The results of this study indicated not only a promising application for the magnetostrictive FeCo clad steel plate as an efficient energy harvester, related to small vibrations, but also the notable feasibility for the formation of integrated units to support high-power trains, automobiles, and electric vehicles.

  104. 傾斜機能圧電複合材料の荷重および温度変化による環境発電特性評価

    森 孝太郎, 前嶋 研祐, 堀辺 忠志, 王 真金, 成田 史生

    M&M材料力学カンファレンス 2018 OS1008 2018年

    出版者・発行元:一般社団法人 日本機械学会

    DOI: 10.1299/jsmemm.2018.os1008  

    eISSN:2424-2845

  105. 非鉛系圧電粒子分散プラスチック複合材料の作製と微風・温度変化発電

    王 真金, 楊 鎮駿, 川上 祥広, 成田 史生

    M&M材料力学カンファレンス 2018 OS1009 2018年

    出版者・発行元:一般社団法人 日本機械学会

    DOI: 10.1299/jsmemm.2018.os1009  

    eISSN:2424-2845

  106. ナノセルロース/絹複合糸の引張特性評価

    呉 宸, 栗田 大樹, 王 真金, 成田 史生

    M&M材料力学カンファレンス 2018 OS1027 2018年

    出版者・発行元:一般社団法人 日本機械学会

    DOI: 10.1299/jsmemm.2018.os1027  

    eISSN:2424-2845

  107. Fabrication of cellulose nanofiber/glass fiber-reinforced composites and their bending behavior evaluation

    Yingmei Xie, Hiroki Kurita, Risa Honda, Kenichi Katabira, Fumio Narita

    33rd Technical Conference of the American Society for Composites 2018 3 1934-1940 2018年

    詳細を見る 詳細を閉じる

    It is required a joint technic with excellent mechanical properties to fabricate glass fiber reinforced plastic (GFRP) components. However, it is well-known that the mechanical jointing often causes the fracture of fiber reinforced plastics. It seems that the adhesive bonding is suitable to joint GFRPs, and it is necessary to develop an adhesive with outstanding mechanical properties. Recently, cellulose nanofibers (CNFs) have been obtained from plants by mechanical and chemical methods and it has been reported that CNFs have remarkable mechanical properties. In this study, we inserted epoxy resin with CNFs between GFRP and investigated its bending behavior, to estimate the capability of epoxy resin with CNFs as an adhesive for GFRPs. The flexural behavior and modulus of GFRP was similar regardless of the inserted part of epoxy resin with CNFs layer in GFRP. The flexural strength of GFRP was drastically increased (up to 600 MPa) by the insert of epoxy resin with CNFs of 5 or 10 wt.%, although that of GFRP was decreased by the insert of epoxy resin with CNFs of 25 wt.%. Therefore, it seems that the epoxy resin with CNFs is available as an adhesive for GFRP. However, it is required the observation of CNFs dispersion in epoxy resin to understand the strengthening mechanism of epoxy resin with CNFs.

  108. Piezoelectric Energy Harvesting Characteristics of Barium Titanate Based Composite Laminates under Cyclic Concentrated Loads 査読有り

    Journal of Composites and Biodegradable Polymers 5 43-47 2017年12月

  109. Three-point bending fatigue of cracked giant magnetostrictive materials under magnetic fields 査読有り

    Fumio Narita, Koji Shikanai, Yasuhide Shindo, Kotaro Mori

    ACTA MECHANICA 228 (11) 3867-3876 2017年11月

    出版者・発行元:SPRINGER WIEN

    DOI: 10.1007/s00707-017-1925-1  

    ISSN:0001-5970

    eISSN:1619-6937

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    This paper investigates the cyclic fatigue behavior in giant magnetostrictive materials with a crack under magnetic fields. Fatigue tests were performed in three-point bending with single-edge precracked-beam specimens, and the number of cycles to failure under sinusoidal mechanical loads and magnetic fields was obtained. A finite element analysis was also carried out, and the energy release rate was calculated. The effect of magnetic fields on the maximum energy release rate versus number of cycles to failure curve was then discussed. In addition, fracture surfaces were examined by scanning electron microscopy and laser microscopy to correlate with fatigue characteristics.

  110. Potential of energy harvesting in barium titanate based laminates from room temperature to cryogenic/high temperatures: measurements and linking phase field and finite element simulations 査読有り

    Fumio Narita, Marina Fox, Kotaro Mori, Hiroki Takeuchi, Takuya Kobayashi, Kenji Omote

    SMART MATERIALS AND STRUCTURES 26 (11) 115027 2017年11月

    出版者・発行元:IOP PUBLISHING LTD

    DOI: 10.1088/1361-665X/aa91a5  

    ISSN:0964-1726

    eISSN:1361-665X

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    This paper studies the energy harvesting characteristics of piezoelectric laminates consisting of barium titanate (BaTiO3) and copper (Cu) from room temperature to cryogenic/ high temperatures both experimentally and numerically. First, the output voltages of the piezoelectric BaTiO3/Cu laminates were measured from room temperature to a cryogenic temperature (77 K). The output power was evaluated for various values of load resistance. The results showed that the maximum output power density is approximately 2240 nW cm(-3). The output voltages of the BaTiO3/Cu laminates were also measured from room temperature to a higher temperature (333 K). To discuss the output voltages of the BaTiO3/Cu laminates due to temperature changes, phase field and finite element simulations were combined. A phase field model for grain growth was used to generate grain structures. The phase field model was then employed for BaTiO3 polycrystals, coupled with the time-dependent Ginzburg-Landau theory and the oxygen vacancies diffusion, to calculate the temperature-dependent piezoelectric coefficient and permittivity. Using these properties, the output voltages of the BaTiO3/Cu laminates from room temperature to both 77 K and 333 K were analyzed by three dimensional finite element methods, and the results are presented for several grain sizes and oxygen vacancy densities. It was found that electricity in the BaTiO3 ceramic layer is generated not only through the piezoelectric effect caused by a thermally induced bending stress but also by the temperature dependence of the BaTiO3 piezoelectric coefficient and permittivity.

  111. Fracture behavior and crack sensing capability of bonded carbon fiber composite joints with carbon nanotube-based polymer adhesive layer under Mode I loading 査読有り

    Tomo Takeda, Fumio Narita

    COMPOSITES SCIENCE AND TECHNOLOGY 146 (7) 26-33 2017年7月

    出版者・発行元:ELSEVIER SCI LTD

    DOI: 10.1016/j.compscitech.2017.04.014  

    ISSN:0266-3538

    eISSN:1879-1050

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    This paper presents a study on the Mode I fracture behavior and crack monitoring of bonded carbon fiber reinforced polymer (CFRP) composite joints with carbon nanotube (CNT)-based polymer adhesive layer. Bonded joints were fabricated using woven carbon/epoxy composite substrates and CNT-based epoxy adhesives. Mode I fracture tests were carried out with double cantilever beam (DCB) bonded joint specimens, and the dependence of the critical energy release rate at the onset of crack growth, i.e., fracture toughness, on the nanotube content in the adhesive layer and the adhesive layer thickness was examined. The electrical resistance of the bonded joint specimens was monitored during the tests. An analytical model based on the electrical conduction mechanism of CNT-based polymers was also employed to describe the electrical resistance change due to crack propagation in the bonded joint specimens, and a good correlation was obtained between the predicted and measured results. The electrical resistance change is found to result in quantitative assessment of crack length based on resistance measurement. It is demonstrated that the bonded CFRP composite joints with CNT-based polymer adhesive layer have improved fracture properties together with crack sensing capability. (C) 2017 Elsevier Ltd. All rights reserved.

  112. Dynamic fatigue of cracked piezoelectric ceramics in three-point bending under electric fields at cryogenic temperatures 査読有り

    Yasuhide Shindo, Fumio Narita, Yuhei Goto

    ENGINEERING FRACTURE MECHANICS 178 258-264 2017年6月

    出版者・発行元:PERGAMON-ELSEVIER SCIENCE LTD

    DOI: 10.1016/j.engfracmech.2017.04.031  

    ISSN:0013-7944

    eISSN:1873-7315

    詳細を見る 詳細を閉じる

    This paper deals with the cryogenic dynamic fatigue behavior of cracked piezoelectric ceramics under electric fields analytically and experimentally. The crack was created normal to the poling direction. Constant load-rate testing was conducted, using three-point bending technique, with the single-edge precracked-beam (SEPB) specimens at room temperature and liquid nitrogen temperature (77 K). The effects of electric fields and loading-rate on the fracture load were examined. Plain strain finite element analysis (FEA) was also performed, and the energy release rate for the permeable crack model was calculated to discuss the effects of loading-rate and temperature on the critical energy release rate. (C) 2017 Elsevier Ltd. All rights reserved.

  113. Energy Harvesting from Temperature Change by Piezoelectric/CNT-based Polymer Composite Laminates 査読有り

    M. Fox, K. Mori, F. Narita

    Proceedings of the JSME 2017 International Conference on Materials and Processing ICMP2017-4342 (4 pages) 2017年6月

  114. Cryogenic static fatigue of cracked piezoelectric ceramics in three-point bending under electric fields 査読有り

    Yasuhide Shindo, Fumio Narita, Yuhei Goto

    ACTA MECHANICA 228 (4) 1407-1413 2017年4月

    出版者・発行元:SPRINGER WIEN

    DOI: 10.1007/s00707-016-1782-3  

    ISSN:0001-5970

    eISSN:1619-6937

    詳細を見る 詳細を閉じる

    This paper studies analytically and experimentally the cryogenic static fatigue behavior of cracked piezoelectric ceramics under electric fields. The crack was created normal to the poling direction. Static fatigue tests were carried out in three-point bending with the single-edge precracked-beam specimens at room temperature and liquid nitrogen temperature (77 K), and times-to-failure under different mechanical loads and electric fields were obtained. Plane strain finite element analysis using temperature-dependent material properties of piezoelectric ceramics was also performed, and the energy release rate for the permeable crack model was calculated. The effects of electric field and temperature on the energy release rate versus lifetime curve are discussed.

  115. Stress-Rate Dependent Output Voltage for Fe29Co71 Magnetostrictive Fiber/Polymer Composites: Fabrication, Experimental Observation and Theoretical Prediction 査読有り

    Fumio Narita, Kenichi Katabira

    MATERIALS TRANSACTIONS 58 (2) 302-304 2017年

    出版者・発行元:JAPAN INST METALS

    DOI: 10.2320/matertrans.M2016410  

    ISSN:1345-9678

    eISSN:1347-5320

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    The Villari effect of magnetostrictive materials, a change in magnetization due to an applied stress, is used for sensor/energy harvesting applications. In this work, magnetostrictive fiber/polymer composites are fabricated for the first time by embedding strong textured Fe-Co fibers in an epoxy matrix, and their stress-rate dependent output voltage characteristics are investigated. Compression tests are first conducted to measure the output voltage of a sample. A simple magnetomechanical coupling model of the magnetostrictive fiber/polymer composite is then established. The output voltage is predicted, and domain wall dynamics is discussed in relation to the macroscopic inverse magnetostrictive response (known as the Villari effect). The results show that the output voltage density of this novel Fe-Co fiber/polymer composite dramatically increases with increasing stress-rate and becomes larger than that of Fe-Ga alloy. Our work represents an important step forward in the development of magnetostrictive sensor and energy harvesting materials.

  116. Inverse Magnetostrictive Effect in Fe29Co71 Wire/Polymer Composites 査読有り

    F. Narita

    Advanced Engineering Materials 19 (1) 1600586 2017年1月

  117. Fracture Behavior of Cracked Giant Magnetostrictive Materials in Three-Point Bending under Magnetic Fields: Strain Energy Density Criterion 査読有り

    Marco Colussi, Filippo Berto, Kotaro Mori, Fumio Narita

    ADVANCED ENGINEERING MATERIALS 18 (12) 2063-2069 2016年12月

    出版者・発行元:WILEY-V C H VERLAG GMBH

    DOI: 10.1002/adem.201500533  

    ISSN:1438-1656

    eISSN:1527-2648

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    In this paper, the fracture behavior of cracked giant magnetostrictive materials has been investigated both numerically and experimentally. Works in literature have been revisited, focusing on iron and rare-earth alloys, such as Terfenol-D. Three-point bending tests have been carried out on precracked specimens and the fracture loads have been measured in the presence and absence of a magnetic field. Recent studies on local stress fields in proximity of crack tips have shown that the Strain Energy Density (SED) can be a robust parameter in the brittle fracture assessment. Coupled-field finite element analyses have then been performed and the effect of the magnetic field on Terfenol-D fracture resistance has been discussed in terms of Energy Release Rate and averaged SED.

  118. Evaluation of Dielectric and Piezoelectric Behavior of Unpoled and Poled Barium Titanate Polycrystals with Oxygen Vacancies using Phase Field Method 査読有り

    F. Narita, T. Kobayashi, Y. Shindo

    International Journal of Smart and Nano Materials 7 (4) 265-275 2016年12月

  119. Effect of the Loading Rate on the Brittle Fracture of Terfenol-D Specimens in Magnetic Field: Strain Energy Density Approach 査読有り

    M. Colussi, F. Berto, K. Mori, F. Narita

    STRENGTH OF MATERIALS 48 (6) 791-800 2016年11月

    出版者・発行元:SPRINGER

    DOI: 10.1007/s11223-017-9826-z  

    ISSN:0039-2316

    eISSN:1573-9325

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    The aim of the present study is to characterize the fracture behavior of the giant magnetostrictive Terfenol-D alloy, both experimentally and numerically. Three-point bending tests have been carried out on single-edge precracked specimens, and fracture loads have been measured at different loading rates, in the presence or absence of a magnetic field. In recent years, it has been shown that the strain energy density (SED), averaged in a finite control volume, can successfully predict brittle failures of cracked, U- and V-notched specimens made of several materials. By performing coupled-field finite element analyses, the effects of the magnetic field and he loading rate on Terfenol-D failures have been analyzed, and the capability of SED criterion to capture these effects has been discussed. A relationship between the SED control volume size and the loading rate has been proposed, and failures have been quite accurately predicted in terms of the averaged SED.

  120. Piezoelectric Vibration Energy Harvesting Characteristics of Barium Titanate Laminates 査読有り

    F. Narita, X. Zhu, Y. Shindo

    Advances in Theoretical and Applied Mechanics 9 (1) 43-54 2016年10月

  121. Mechanical Property Evaluation of Triaxial Woven CFRP from Low to High Temperatures and Multi-Functionalization of Composites with Modified Resin 査読有り

    K. Nakajima, S. Kumagai, A. Watanabe, F. Narita

    Proceedings, The 5th Asian Conference on Mechanics of Functional Materials and Structures 198-201 2016年10月

  122. Fabrication and Magneto-Mechanical Behavior of Polymer Matrix/Terfenol-D Hybrid Composites 査読有り

    K. Katabira, F. Narita

    Proceedings, The 5th Asian Conference on Mechanics of Functional Materials and Structures 202-205 2016年10月

  123. Crack Self-Sensing of CNT-based Epoxy Bonded CFRP Joints under Mode I Loading 査読有り

    T. Takeda, F. Narita

    Proceedings, The 10th International Conference on Fracture and Strength of Solids 2016年8月

  124. Three-Point Bending Fracture Behavior of Cracked Giant Magnetostrictive Materials Under Magnetic Fields 査読有り

    Fumio Narita, Koji Shikanai, Yasuhide Shindo, Kotaro Mori

    JOURNAL OF TESTING AND EVALUATION 44 (4) 1454-1460 2016年7月

    出版者・発行元:AMER SOC TESTING MATERIALS

    DOI: 10.1520/JTE20140439  

    ISSN:0090-3973

    eISSN:1945-7553

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    This paper numerically and experimentally investigated the three-point bending fracture behavior of cracked giant magnetostrictive materials under magnetic fields. Three-point bending fracture tests were carried out using the single-edge precracked-beam (SEPB) specimens, and the fracture loads were measured under magnetic fields. The crack was created normal to the direction of easy magnetization. Plane strain finite element analysis (FEA) was also performed, and the effect of magnetic fields on the energy release rate and on the apparent fracture toughness (critical energy release rate obtained using the fracture load) was discussed in detail. To the author's knowledge, this work is the first attempt to study the effect of magnetic fields on the fracture behavior of giant magnetostrictive materials.

  125. Strain Energy Density Based Assessment of Cracked Terfenol-D Specimens under Magnetic Field and Different Loading Rates 査読有り

    M. Colussi, F. Berto, K. Mori, F. Narita

    Structural Integrility Procedia 2 1837-1844 2016年6月

  126. Deformation and failure of hybrid beams consisting of woven carbon fiber composite and shape memory polymer layers under flexural loading 査読有り

    Tomo Takeda, Fumio Narita, Yasuhide Shindo

    JOURNAL OF SANDWICH STRUCTURES & MATERIALS 18 (1) 113-128 2016年1月

    出版者・発行元:SAGE PUBLICATIONS LTD

    DOI: 10.1177/1099636215607395  

    ISSN:1099-6362

    eISSN:1530-7972

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    This paper investigates the deformation and failure behaviors of hybrid layered beams consisting of woven carbon fiber-reinforced polymer composite and shape memory polymer layers subjected to flexural loading. The temperature of the shape memory polymer layer was controlled by using electrical resistive heating of the woven carbon fiber-reinforced polymer layers. Three-point bending tests were then conducted on the layered beams, and the variation in the beam flexural stiffness with temperature was examined. The failure characteristics of the layered beams were also studied by microscopic observations of the tested specimens. In addition, a three-dimensional finite element analysis was performed to determine the beam flexural stiffness and the stress states in the layered beams. The predicted flexural stiffnesses were found to be in reasonable agreement with the experimental data, and the stress results were used to better understand and explain the experimental findings on the beam failure. The present results can be useful in the design and developments of high performance material systems with variable stiffness properties for aerospace morphing applications.

  127. Detection and response characteristics of giant magnetostrictive/piezoelectric laminated cantilevers under cyclic bending 査読有り

    Kotaro Mori, Yasuhide Shindo, Fumio Narita, So Okura

    MECHANICS OF ADVANCED MATERIALS AND STRUCTURES 23 (2) 180-186 2016年

    出版者・発行元:TAYLOR & FRANCIS INC

    DOI: 10.1080/15376494.2014.949924  

    ISSN:1537-6494

    eISSN:1537-6532

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    We examine the detection and response characteristics of giant magnetostrictive/piezoelectric laminated cantilevers under cyclic bending in a combined numerical and experimental approach. The laminate is fabricated using thin Terfenol-D and PZT layers. Three-dimensional finite element analysis was conducted, and the dynamic electromagneto-mechanical fields in the two-layered magnetostrictive/piezoelectric laminate were predicted by introducing a second-order magnetoelastic constant of Terfenol-D. The tip deflection, induced voltage, and induced magnetic field were also measured, and experimental data were compared with numerical simulations to verify the model. The effects of load ratio and frequency on the dynamic electromagneto-mechanical fields were then discussed in detail. The finite element method is shown to be capable of estimating the dynamic electromagneto-mechanical fields in the giant magnetostrictive/piezoelectric laminated cantilevers, making it a useful tool for designing future electronic devices with self-sensing or energy harvesting capabilities.

  128. Electromechanical response of polycarbonate-CNT/PZT laminates subjected to cyclic bending 査読有り

    Fumio Narita, So Okura, Yasuhide Shindo, Tomo Takeda

    INTERNATIONAL JOURNAL OF MATERIALS & PRODUCT TECHNOLOGY 52 (3-4) 276-285 2016年

    出版者・発行元:INDERSCIENCE ENTERPRISES LTD

    DOI: 10.1504/IJMPT.2016.075495  

    ISSN:0268-1900

    eISSN:1741-5209

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    This paper deals with the electromechanical behaviour of polymer-carbon nanotube (CNT)/piezoelectric laminates under cyclic bending. The laminate was fabricated using thin polycarbonate-multi-walled carbon nanotube (MWNT) and lead zirconate titanate (PZT) layers. The three-point bending tests were performed on the polycarbonate-MWNT/PZT laminates, and the output voltage due to cyclic mechanical loads was measured. The output power was then calculated, and the dependence of the output power on the nanotube content, material dimensions and loading conditions (e.g., frequency) was discussed in detail. It was found that there is an optimum value of the nanotube content for which the output power is maximised.

  129. Recent results on the brittle fracture of terfenol-D specimens under magnetic field 査読有り

    Marco Colussi, Filippo Berto, Kotaro Mori, Fumio Narita

    American Journal of Engineering and Applied Sciences 9 (4) 1239-1246 2016年

    出版者・発行元:Science Publications

    DOI: 10.3844/ajeassp.2016.1239.1246  

    ISSN:1941-7039 1941-7020

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    The following investigation has the purpose of describing, both experimentally and numerically, the fracture behavior of a giant magnetostrictive alloy commercially known as Terfenol-D. Single-edge precracked specimens have been analyzed via three-point bending tests, measuring fracture loads in the presence and absence of a magnetic field at various loading rates. The Strain Energy Density (SED), averaged in a finite control volume, has recently proved to be an excellent method of predicting brittle failures of cracked, U- and V-notched specimens made out of different materials. The effects of the magnetic field and of the loading rate on Terfenol-D failures have been studied, as well as discussing the ability of SED criterion to seize these effects, by performing coupled-field finite element analyses. Finally, a relationship between the size of the SED’s control volume and the loading rate has been proposed and failures have then been estimated in terms of averaged SED.

  130. Characteristics of vibration energy harvesting using giant magnetostrictive cantilevers with resonant tuning 査読有り

    Kotaro Mori, Tadashi Horibe, Shigekazu Ishikawa, Yasuhide Shindo, Fumio Narita

    SMART MATERIALS AND STRUCTURES 24 (12) 125032 (7 pages) 2015年12月

    出版者・発行元:IOP PUBLISHING LTD

    DOI: 10.1088/0964-1726/24/12/125032  

    ISSN:0964-1726

    eISSN:1361-665X

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    This work deals with the dynamic bending and energy harvesting characteristics of giant magnetostrictive cantilevers with resonant tuning both numerically and experimentally. The giant magnetostrictive cantilever is fabricated using a thin Terfenol-D layer, SUS layer, movable proof mass, etc, and, is designed to automatically adjust its own resonant frequency to match the external vibration frequency in real time. Three-dimensional finite element analysis was conducted, and the resonant frequency, induced voltage and stress in the magnetostrictive cantilevers were predicted. The resonant frequency and induced voltage were also measured, and comparison was made between simulation and experiment. The time-varying behavior and self-tuning ability are discussed in detail.

  131. Detection and Response Characteristics of Clamped-Free Giant Magnetostrictive/Piezoelectric Laminates under Concentrated Loading 査読有り

    K. Mori, F. Narita, Y. Shindo

    AIMS Materials Science 4 (2) 401-413 2015年10月

  132. Cryogenic through-thickness tensile characterization of plain woven glass/epoxy composite laminates using cross specimens: Experimental test and finite element analysis 査読有り

    Tomo Takeda, Fumio Narita, Yasuhide Shindo, Kazuaki Sanada

    COMPOSITES PART B-ENGINEERING 78 42-49 2015年9月

    出版者・発行元:ELSEVIER SCI LTD

    DOI: 10.1016/j.compositesb.2015.03.076  

    ISSN:1359-8368

    eISSN:1879-1069

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    This paper investigates the through-thickness tensile behavior of woven glass fiber reinforced polymer (GFRP) composite laminates at cryogenic temperatures. Tensile tests were carried out with cross specimens at room temperature and liquid nitrogen temperature (77 K), and the through-thickness elastic and strength properties of the woven GFRP laminates were evaluated. The failure characteristics of the woven GFRP laminates were also studied by optical and laser scanning microscopy observations. A three-dimensional finite element analysis was performed to calculate the stress distributions in the cross specimens, and the failure conditions of the specimens were examined. It is found that the cross specimen is suitable for the cryogenic through-thickness tensile characterization of laminated composite materials. In addition, the through-thickness Young's modulus of the woven GFRP composite laminates is dominated by the properties of the matrix polymer in the given temperature, while the tensile strength is characterized by both, the fiber to matrix interface energy and the cohesion energy of the matrix polymer. (C) 2015 Elsevier Ltd. All rights reserved.

  133. Phase field simulation on the electromechanical response of poled barium titanate polycrystals with oxygen vacancies 査読有り

    Yasuhide Shindo, Fumio Narita, Takuya Kobayashi

    JOURNAL OF APPLIED PHYSICS 117 (23) 234103 2015年6月

    出版者・発行元:AMER INST PHYSICS

    DOI: 10.1063/1.4922720  

    ISSN:0021-8979

    eISSN:1089-7550

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    This work investigates the electromechanical response of poled barium titanate (BaTiO3) polycrystals with oxygen vacancies at room temperature. A phase field model is developed for ferroelectric polycrystals, coupled with the time-dependent Ginzburg-Landau theory and the oxygen vacancies diffusion, to demonstrate the interaction between oxygen vacancies and domain evolutions. To generate grain structures, the phase field model for grain growth is also employed. The hysteresis loop (polarization vs electric field curve) and butterfly loop (strain vs electric field curve) are computed, and the effects of grain size and oxygen vacancy density on the dielectric and piezoelectric properties of the BaTiO3 polycrystals are discussed. (C) 2015 AIP Publishing LLC.

  134. Piezoelectric Detection and Response Characteristics of Barium Titanate Unimorph Cantilevers under AC Electric Fields 査読有り

    F. Narita, Y. Shindo

    International Journal of Metallurgical & Materials Engineering 1 (1) 103 2015年4月

  135. Fatigue failure and electrical resistance behaviors of carbon nanotube-based polymer composites under uniaxial tension-tension loading in a cryogenic environment 査読有り

    Tomo Takeda, Yasuhide Shindo, Zhijuan Wei, Yu Kuronuma, Fumio Narita

    JOURNAL OF COMPOSITE MATERIALS 49 (4) 457-463 2015年2月

    出版者・発行元:SAGE PUBLICATIONS LTD

    DOI: 10.1177/0021998314521059  

    ISSN:0021-9983

    eISSN:1530-793X

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    This paper investigates the fatigue failure and electrical resistance behaviors of carbon nanotube-based polymer composites at cryogenic temperatures. Tension-tension fatigue tests were performed on carbon nanotube /polycarbonate composites at room temperature and liquid nitrogen temperature (77K), and the electrical resistance of the specimens was monitored during the tests. Based on the obtained results, the dependence of the mechanical and electrical responses of the nanocomposites on the temperature and the nanotube content was studied. Microscopic examinations were also carried out on the specimen fracture surfaces, and the failure mechanisms of the nanocomposites were discussed.

  136. Flexural stiffness variations of woven carbon fiber composite/shape memory polymer hybrid layered beams 査読有り

    Tomo Takeda, Yasuhide Shindo, Fumio Narita

    JOURNAL OF COMPOSITE MATERIALS 49 (2) 209-216 2015年1月

    出版者・発行元:SAGE PUBLICATIONS LTD

    DOI: 10.1177/0021998313515458  

    ISSN:0021-9983

    eISSN:1530-793X

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    This paper studies the flexural stiffness controllability of hybrid layered beams with woven carbon fiber reinforced polymer composite and shape memory polymer layers. The temperature of the shape memory polymer layer was controlled using electrical resistive heating of the woven carbon fiber reinforced polymer layers. Flexure tests were then conducted on the layered cantilever beams, and the temperature dependence of the beam flexural stiffness was examined. A three-dimensional finite element analysis was also performed to predict the flexural response of the layered beams, and a good correlation was observed between the predicted and measured results for the flexural stiffness. In addition, the deformation states in the layered beams were determined numerically and discussed in detail.

  137. Loading Rate-Dependent Fracture Properties and Electrical Resistance-Based Crack Growth Monitoring of Polycarbonate Reinforced with Carbon Nanotubes Under Tension 査読有り

    Fumio Narita, Yasuhide Shindo, Tomo Takeda, Yu Kuronuma, Kazuaki Sanada

    JOURNAL OF TESTING AND EVALUATION 43 (1) 115-122 2015年1月

    出版者・発行元:AMER SOC TESTING MATERIALS

    DOI: 10.1520/JTE20130334  

    ISSN:0090-3973

    eISSN:1945-7553

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    This paper presents a combined numerical-experimental study on the loading rate-dependent fracture behavior of cracked carbon nanotube (CNT)-based polymer composites under tension. Tensile tests at various loading rates were conducted on single-edge cracked plate specimens of CNT/polycarbonate composites. The electrical resistance change of the composite specimens was utilized to capture the crack behavior during the tests. An elastic-plastic finite element analysis was also employed to determine the fracture properties by means of the J-integral. In addition, scanning electron microscopy (SEM) observation was implemented to assess the fracture mechanisms of the CNT-based polymer composites under the different loading rates.

  138. Electromechanical bending response of PZT/CNT-based polymer laminates subjected to concentrated load 査読有り

    Yasuhide Shindo, Fumio Narita, So Okura, Tomo Takeda, Chengju Fu

    INTERNATIONAL JOURNAL OF MECHANICS AND MATERIALS IN DESIGN 10 (2) 193-197 2014年6月

    出版者・発行元:SPRINGER HEIDELBERG

    DOI: 10.1007/s10999-014-9240-7  

    ISSN:1569-1713

    eISSN:1573-8841

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    This paper presents the electromechanical behavior of piezoelectric/carbon nanotube (CNT)-based polymer laminates under three-point bending. The laminate was fabricated using thin lead zirconate titanate (PZT) and multi-walled carbon nanotube (MWNT)-based polycarbonate layers. The three-point bending tests were conducted on the PZT/MWNT-based polycarbonate laminates, and the dependence of the displacement and output voltage due to mechanical loads on the nanotube content and the material dimensions were measured and discussed. The output power was then calculated. This study showed that the piezoelectric/CNT-based polymer laminates can generate power without external load resistance.

  139. Mixed-mode I/III fatigue delamination growth in woven glass/epoxy composite laminates at cryogenic temperatures 査読有り

    Masaya Miura, Yasuhide Shindo, Tomo Takeda, Fumio Narita

    JOURNAL OF COMPOSITE MATERIALS 48 (10) 1251-1259 2014年5月

    出版者・発行元:SAGE PUBLICATIONS LTD

    DOI: 10.1177/0021998313484951  

    ISSN:0021-9983

    eISSN:1530-793X

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    This work deals with the delamination growth behavior in woven glass fiber reinforced polymer (GFRP) composite laminates under mixed-mode I/III fatigue loading at cryogenic temperatures. Fatigue delamination tests were carried out with eight-point bending plate (8PBP) specimens at room temperature, liquid nitrogen temperature (77K), and liquid helium temperature (4K), and the delamination growth rate data were expressed in terms of the energy release rate range during fatigue loading. The energy release rate was calculated using the three-dimensional finite element method. Moreover, the fracture surface characteristics of the woven GFRP laminates under mixed-mode I/III fatigue loading were examined by scanning electron microscopy (SEM).

  140. Interlaminar Shear and Electrical Resistance Responses of Woven-Carbon-Fiber-Reinforced-Polymer Composite Laminates at Cryogenic Temperatures From Cyclic Short Beam Shear Tests 査読有り

    Yasuhide Shindo, Tomo Takeda, Fumio Narita, Tatsuya Fukuzaki

    JOURNAL OF TESTING AND EVALUATION 42 (3) 573-580 2014年5月

    出版者・発行元:AMER SOC TESTING MATERIALS

    DOI: 10.1520/JTE20130082  

    ISSN:0090-3973

    eISSN:1945-7553

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    This paper studies the interlaminar shear and electrical resistance responses of woven-carbon-fiber-reinforced-polymer (CFRP) composite laminates subjected to fatigue loading at cryogenic temperatures. Fatigue tests were conducted on the composite specimens at room temperature and liquid-hydrogen temperature (20 K) using the short beam shear method, and measurements of the specimen electrical resistance were made during the tests. Also, the tested specimens were examined by microscopy to observe the damage and the failure mode. In addition, a finite-element analysis was performed to examine the stress distributions in the short beam shear specimens. The dependence of the interlaminar shear fatigue performance of the woven-CFRP laminates on the temperature was discussed, and the applicability of the electrical resistance method for assessing the fatigue failure was demonstrated.

  141. Electromechanical response of multilayer piezoelectric actuators for fuel injectors at high temperatures 査読有り

    Fumio Narita, Ryohei Hasegawa, Yasuhide Shindo

    JOURNAL OF APPLIED PHYSICS 115 (18) 184103 2014年5月

    出版者・発行元:AMER INST PHYSICS

    DOI: 10.1063/1.4875487  

    ISSN:0021-8979

    eISSN:1089-7550

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    This paper studies the electromechanical response of multilayer piezoelectric actuators from room to high temperatures for fuel injector applications. A phenomenological model of depolarization at high temperatures was proposed, and the temperature dependent piezoelectric coefficients were obtained. The nonlinear electromechanical fields of the multilayer piezoelectric actuators due to the depolarization at high temperatures were then calculated by the finite element method. In addition, experimental results on the electric field induced strain at high temperatures were presented to validate the predictions. (C) 2014 AIP Publishing LLC.

  142. Flexural fatigue performance and electrical resistance response of carbon nanotube-based polymer composites at cryogenic temperatures 査読有り

    Zhijuan Wei, Tomo Takeda, Fumio Narita, Yasuhide Shindo

    CRYOGENICS 59 44-48 2014年1月

    出版者・発行元:ELSEVIER SCI LTD

    DOI: 10.1016/j.cryogenics.2013.12.004  

    ISSN:0011-2275

    eISSN:1879-2235

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    We study the flexural failure and electrical resistance change of carbon nanotube (CNT)-based polymer composites under cyclic loading at cryogenic temperatures. Fatigue tests were performed on CNT/polycarbonate composites at room temperature and liquid nitrogen temperature (77 K) using the three-point bending method, and the measurements of the specimen electrical resistance were made during the tests. Also, the specimen fracture surfaces were examined by scanning electron microscopy (SEM) to verify the failure mechanisms of the nanocomposites. The dependence of the mechanical and electrical responses of the nanocomposites on the temperature and the nanotube content was then discussed. (C) 2013 Elsevier Ltd. All rights reserved.

  143. Short beam interlaminar shear behavior and electrical resistance-based damage self-sensing of woven carbon/epoxy composite laminates in a cryogenic environment 査読有り

    Tomo Takeda, Yasuhide Shindo, Tatsuya Fukuzaki, Fumio Narita

    JOURNAL OF COMPOSITE MATERIALS 48 (1) 119-128 2014年1月

    出版者・発行元:SAGE PUBLICATIONS LTD

    DOI: 10.1177/0021998312469240  

    ISSN:0021-9983

    eISSN:1530-793X

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    This article investigates the interlaminar shear behavior and damage detection of woven carbon fiber reinforced polymer composite laminates at cryogenic temperatures. Short beam shear tests were performed at room temperature and liquid hydrogen temperature (20K), and the temperature dependence of the apparent interlaminar shear strength was examined. The electrical resistance of the composite specimens was also monitored during the tests. A detailed observation of the tested specimens was made to assess the damage, and the relationship between the damage and the electrical resistance was discussed. In addition, the stress, strain and current density distributions in the short beam shear specimens were determined by the finite element method. The numerical results were used to better understand and explain the experimental findings.

  144. Cryogenic fracture of cracked piezoelectric ceramics in three-point bending under electric fields 査読有り

    Yasuhide Shindo, Fumio Narita

    Acta Mechanica 225 (4-5) 1313-1321 2014年

    出版者・発行元:Springer-Verlag Wien

    DOI: 10.1007/s00707-013-1047-3  

    ISSN:0001-5970

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    This paper investigates theoretically and experimentally the cryogenic fracture behavior of cracked piezoelectric ceramics under electric fields. Fracture tests were performed in three-point bending with the single-edge precracked-beam specimens at room temperature and liquid nitrogen temperature (77 K), and the fracture loads under electric fields were obtained. Plane strain finite element analysis was also carried out using temperature-dependent material properties of the piezoelectric ceramics, and the dependence of the energy release rate on the electric field and temperature was discussed. In addition, possible mechanisms for cryogenic fracture were examined by scanning electron microscopy. © 2014 Springer-Verlag Wien.

  145. Dynamic bending/torsion and output power of S-shaped piezoelectric energy harvesters 査読有り

    Yasuhide Shindo, Fumio Narita

    International Journal of Mechanics and Materials in Design 10 (3) 305-311 2014年

    出版者・発行元:Kluwer Academic Publishers

    DOI: 10.1007/s10999-014-9247-0  

    ISSN:1573-8841 1569-1713

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    This paper studies the dynamic electromechanical response of S-shaped piezoelectric energy harvesters both numerically and experimentally. The resonant frequency and output voltage of the harvesters excited by bending/torsion vibration were analyzed by three dimensional finite element method. The resonant frequency and output voltage were also measured, and a comparison was made between analysis and experiment. The effects of waviness ratio, proof mass and load resistance on the dynamic electromechanical fields and output power were then discussed in detail.

  146. Cryogenic mechanical properties of woven glass/epoxy composites modified with multi-walled carbon nanotube and n-butyl glycidyl ether under tensile static and cyclic loadings 査読有り

    Tomo Takeda, Weiwei Fan, Qing-Ping Feng, Shao-Yun Fu, Fumio Narita, Yasuhide Shindo

    CRYOGENICS 58 33-37 2013年12月

    出版者・発行元:ELSEVIER SCI LTD

    DOI: 10.1016/j.cryogenics.2013.09.005  

    ISSN:0011-2275

    eISSN:1879-2235

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    This paper investigates the mechanical properties of woven glass/epoxy composites modified with multi-walled nanotube (MWNT) and n-butyl glycidyl ether (BGE) under tensile static and cyclic loadings at cryogenic temperatures. Tensile tests were conducted at liquid nitrogen temperature (77 K), and the tensile properties of the composites were evaluated. Tension-tension fatigue tests were also performed on the composites at 77 K in order to assess their fatigue performance. Failed specimens were examined by microscopy to verify the failure mechanisms. (C) 2013 Elsevier Ltd. All rights reserved.

  147. Fatigue delamination growth in woven glass/epoxy composite laminates under mixed-mode II/III loading conditions at cryogenic temperatures 査読有り

    Tomo Takeda, Masaya Miura, Yasuhide Shindo, Fumio Narita

    CRYOGENICS 58 55-61 2013年12月

    出版者・発行元:ELSEVIER SCI LTD

    DOI: 10.1016/j.cryogenics.2013.10.001  

    ISSN:0011-2275

    eISSN:1879-2235

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    We investigate the cryogenic delamination growth behavior in woven glass fiber reinforced polymer (GFRP) composite laminates under mixed-mode II/III fatigue loading. Fatigue delamination tests were conducted with six-point bending plate (6PBP) specimens at room temperature, liquid nitrogen temperature (77 K) and liquid helium temperature (4 K), and the delamination growth rate data for various mixed-mode ratios of Modes II and III were obtained. The energy release rate was evaluated using the three-dimensional finite element method. In addition, the fatigue delamination growth mechanisms were characterized by scanning electron microscopic observations of the specimen fracture surfaces. (C) 2013 Elsevier Ltd. All rights reserved.

  148. Effects of electric field and poling on the mode I energy release rate in cracked piezoelectric ceramics at cryogenic temperatures 招待有り 査読有り

    Yasuhide Shindo, Fumio Narita, Masayuki Sato

    ACTA MECHANICA 224 (11) 2547-2558 2013年11月

    出版者・発行元:SPRINGER WIEN

    DOI: 10.1007/s00707-013-0949-4  

    ISSN:0001-5970

    eISSN:1619-6937

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    We discuss the mode I energy release rate of a rectangular piezoelectric material with a crack under electromechanical loading at cryogenic temperatures. A crack was created normal or parallel to the poling direction, and electric fields were applied parallel or normal to the poling. A plane strain finite element analysis was carried out, and the effects of electric field and localized polarization switching on the energy release rate were discussed for the piezoelectric ceramics at cryogenic temperatures.

  149. Strength characterization of woven glass/epoxy composites under tensile fatigue loading at cryogenic temperatures using open hole specimens 査読有り

    Yasuhide Shindo, Tomo Takeda, Fumio Narita, Satoru Yamaki

    JOURNAL OF COMPOSITE MATERIALS 47 (22) 2885-2893 2013年10月

    出版者・発行元:SAGE PUBLICATIONS LTD

    DOI: 10.1177/0021998312459870  

    ISSN:0021-9983

    eISSN:1530-793X

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    In this article, we investigate the strength characteristics of woven glass fiber reinforced polymer composite laminates subjected to tensile fatigue loading at cryogenic temperatures using the open hole specimens. Tension-tension fatigue tests were conducted on the open hole specimens of the woven glass fiber reinforced polymer laminates at room temperature, liquid nitrogen temperature (77K) and liquid helium temperature (4K), and microscopic observations of damage around the hole were made on failed specimens. A numerical procedure based on the finite element method was then applied to evaluate the fatigue strength of the unnotched woven glass fiber reinforced polymer laminates using the experimentally applied load and the length of the hole edge damage zone. The obtained results were compared with the existing experimental data from the unnotched specimens. It was demonstrated that the presented combined numerical-experimental method was effective for the determination of the fatigue properties of the woven glass fiber reinforced polymer laminates at cryogenic temperatures.

  150. Effects of electric field and poling on the fatigue of cracked piezoelectric ceramics in cyclic three-point bending 査読有り

    Yasuhide Shindo, Masayuki Sato, Fumio Narita

    Journal of Electroceramics 31 (1-2) 8-14 2013年10月

    DOI: 10.1007/s10832-013-9798-8  

    ISSN:1385-3449 1573-8663

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    This paper deals with the fatigue behavior of cracked piezoelectric ceramics in cyclic bending under electric fields both numerically and experimentally. Fatigue tests were carried out in three-point bending with the single-edge precracked-beam specimens. The crack was created normal to the poling direction. Number of cycles to failure was measured under different electric fields. A plane strain finite element analysis was also performed, and the effect of polarization switching on the energy release rate was discussed under a high negative electric field. In addition, possible mechanisms for crack growth were discussed by scanning electron microscope examination of the fracture surface of the piezoelectric ceramics. © 2013 Springer Science+Business Media New York.

  151. Fatigue Behavior of Cracked Piezoelectric Ceramics in Cyclic Three-Point Bending under AC Electric Fields 査読有り

    F. Narita, Y. Shindo, M. Sato

    Journal of Solid Mechanics and Materials Engineering 7 (5) 530-539 2013年9月

    出版者・発行元:The Japan Society of Mechanical Engineers

    DOI: 10.1299/jmmp.7.530  

    ISSN:1880-9871

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    This paper investigates analytically and experimentally the cyclic fatigue behavior in piezoelectric ceramics with a crack normal to the poling under alternating current (AC) electric fields. Fatigue tests were performed in three-point bending with the single-edge precracked-beam (SEPB) specimens, and numbers of cycles to failure under sinusoidal mechanical loads and AC electric fields were obtained. Finite element analysis was also conducted using a phenomenological model of domain wall motion, and the energy release rate was calculated. The effect of AC electric fields on the maximum energy release rate versus number of cycles to failure curve was then discussed. In addition, the fracture surfaces were examined by scanning electron microscopy to correlate with fatigue characteristics. The important conclusions are that when the AC electric fields with the same phase of the sinusoidal mechanical loads are applied to the cracked piezoelectric ceramics, the number of cycles to failure becomes smaller and the slope of the maximum energy release rate versus number of cycles to failure becomes steeper.

  152. Cryogenic interlaminar fracture properties of woven glass/epoxy composite laminates under mixed-mode I/III loading conditions 査読有り

    Masaya Miura, Yasuhide Shindo, Tomo Takeda, Fumio Narita

    Applied Composite Materials 20 (4) 587-599 2013年8月

    DOI: 10.1007/s10443-012-9290-7  

    ISSN:0929-189X

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    We characterize the combined Mode I and Mode III delamination fracture behavior of woven glass fiber reinforced polymer (GFRP) composite laminates at cryogenic temperatures. The eight-point bending plate (8PBP) tests were conducted at room temperature, liquid nitrogen temperature (77 K) and liquid helium temperature (4 K) using a new test fixture. A three-dimensional finite element analysis was also performed to calculate the energy release rate distribution along the delamination front, and the delamination fracture toughnesses were evaluated for various mixed-mode I/III ratios. Furthermore, the microscopic examinations of the fracture surfaces were carried out with scanning electron microscopy (SEM), and the mixed-mode I/III delamination fracture mechanisms in the woven GFRP laminates at cryogenic temperatures were assessed. The fracture properties were then correlated with the observed characteristics. © 2012 Springer Science+Business Media B.V.

  153. Piezoelectric control of delamination response in woven fabric composites under mode i loading 招待有り 査読有り

    Yasuhide Shindo, Masaya Miura, Tomo Takeda, Fumio Narita, Shunji Watanabe

    Acta Mechanica 224 (6) 1315-1322 2013年6月

    DOI: 10.1007/s00707-013-0862-x  

    ISSN:0001-5970

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    This paper investigates the application of piezoelectric actuators to control the delamination response in woven fabric composites subjected to Mode I loading. Experiments were conducted on a double cantilever beam (DCB) specimen of woven glass fiber reinforced polymer (GFRP) composite laminates with piezoelectric ceramic actuators bonded on the surfaces, in order to evaluate the dependence of the delamination behavior on the applied electric fields. A finite element analysis of the DCB specimen with surface-bonded actuators was also performed, and a comparison was made between the finite element predictions and the test results. In addition, the effect of the actuator location on the effectiveness of the piezoelectric control was examined numerically. © 2013 Springer-Verlag Wien.

  154. Controllability of cryogenic Mode I delamination behavior in woven fabric composites using piezoelectric actuators 査読有り

    Yasuhide Shindo, Shunji Watanabe, Tomo Takeda, Masaya Miura, Fumio Narita

    ENGINEERING FRACTURE MECHANICS 102 171-179 2013年4月

    出版者・発行元:PERGAMON-ELSEVIER SCIENCE LTD

    DOI: 10.1016/j.engfracmech.2013.01.013  

    ISSN:0013-7944

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    This paper investigates experimentally and numerically the delamination behavior in woven glass fiber reinforced polymer (GFRP) composite laminates with surface-bonded piezoelectric ceramic actuators under Mode I loading at cryogenic temperatures. The piezoelectric actuators were used to control the delamination behavior in a composite double cantilever beam (DCB) specimen, and tests were performed at liquid nitrogen temperature (77 K). The finite element analysis of the DCB specimen with piezoelectric actuators was also carried out using temperature-dependent material properties of both the woven GFRP laminates and the piezoelectric ceramics, and the numerical predictions were compared with the experimental data. The dependence of the Mode I delamination behavior on the applied electric fields and the temperature was examined based on the experimental and numerical results, and the feasibility of piezoelectric control of cryogenic delamination behavior in composite laminates was demonstrated. (C) 2013 Elsevier Ltd. All rights reserved.

  155. Cryogenic Electromechanical Response of Multilayer PZT Actuators in Hydrogen Fuel Injectors 招待有り 査読有り

    Y. Shindo, F. Narita

    Proceedings of ITALY’2013 Twelve AES-ATEMA International Conference on "Advances and Trends in Engineering Materials and their Applications", Edited by Yehia Haddad and Alfonso Nappi 81-87 2013年4月

  156. Fracture and Fatigue Behavior of Cracked Piezoelectric Ceramics under Electric Fields 招待有り 査読有り

    Y. Shindo, F. Narita

    AES Technical Reviews Journals, PART C: International Journal of Advances and Trends in Engineering Materials and their Applications 1 (1) 13-20 2013年1月

  157. Crack and electrical resistance behaviors of carbon nanotube-based polymer composites under mixed-mode I/II loading 査読有り

    Tomo Takeda, Yasuhide Shindo, Fumitsugu Naraoka, Yu Kuronuma, Fumio Narita

    Materials Transactions 54 (7) 1105-1109 2013年

    DOI: 10.2320/matertrans.M2013080  

    ISSN:1345-9678

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    This paper studies the crack and electrical resistance behaviors of carbon nanotube (CNT)-based polymer composites under mixed-mode I/II loading by theoretical and experimental approaches. Mixed-mode fracture tests were performed on single-edge cracked plate specimens of the nanocomposites, and the electrical resistance of the specimens was measured. Also, the crack growth direction was predicted by a fracture mechanics approach. In addition, an analytical model based on the electrical conduction mechanism of CNT-based composites was developed to describe the electrical resistance change as a result of inclined crack growth. The predictions on the crack growth direction and the crack induced resistance change were compared with the experimental data, and good agreements were found. © 2013 The Japan Institute of Metals and Materials.

  158. Numerical and experimental study on the response of multi-walled carbon nanotube/polymer composites under compressive loading 招待有り 査読有り

    T. Takeda, F. Narita, Y. Kuronuma, Y. Shindo

    International Journal of Materials and Structural Integrity 7 (1-3) 4-21 2013年1月1日

    DOI: 10.1504/IJMSI.2013.055103  

    ISSN:1745-0055 1745-0063

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    In this paper, we present the numerical and experimental characterisation of the compressive behaviour of multi-walled carbon nanotube (MWNT)/polymer composites. Compression tests were conducted on MWNT/polymer composites at room temperature and liquid nitrogen temperature (77 K) to identify the effect of nanotube addition on their macroscopic behaviour. Multiscale analysis was also performed to predict the composite response to compressive loading. Three-dimensional finite elements were used to model the representative volume element (RVE) of MWNT/polymer composites, and the nanoscale structure of the MWNT was incorporated by determining its elastic properties using analytical molecular structural mechanics models. It was found that the elastic modulus in compression is improved effectively by adding MWNTs. The correlation between the numerical and experimental results presents some basic insights regarding the reinforcing mechanisms in the nanocomposites under compression. Copyright © 2013 Inderscience Enterprises Ltd.

  159. Interlaminar fracture characterization of woven glass/epoxy composites under mixed-mode II/III loading conditions at cryogenic temperatures 査読有り

    Masaya Miura, Yasuhide Shindo, Tomo Takeda, Fumio Narita

    ENGINEERING FRACTURE MECHANICS 96 615-625 2012年12月

    出版者・発行元:PERGAMON-ELSEVIER SCIENCE LTD

    DOI: 10.1016/j.engfracmech.2012.09.019  

    ISSN:0013-7944

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    This paper presents a study of the delamination fracture behavior of woven glass fiber reinforced polymer (GFRP) composite laminates under combined Modes II and III loading at cryogenic temperatures. Mixed-mode II/III delamination fracture tests were carried out with six-point bending plate (6PBP) specimens at room temperature, liquid nitrogen temperature (77 K) and liquid helium temperature (4 K). A three-dimensional finite element analysis was also performed to determine the critical energy release rate at the onset of delamination growth, i.e., fracture toughness, and the dependence of the fracture toughness on the temperature and the mixed-mode II/III ratio was discussed. In addition, scanning electron microscopic observations of the fracture surfaces were conducted to examine the cryogenic fracture mechanisms in the woven GFRP laminates under mixed-mode II/III conditions. (C) 2012 Elsevier Ltd. All rights reserved.

  160. Three-dimensional stress analysis of cracked satin woven carbon fiber reinforced/polymer composites under tension at cryogenic temperatures 査読有り

    Tomo Takeda, Yasuhide Shindo, Shinya Watanabe, Fumio Narita

    CRYOGENICS 52 (12) 784-792 2012年12月

    出版者・発行元:ELSEVIER SCI LTD

    DOI: 10.1016/j.cryogenics.2012.09.002  

    ISSN:0011-2275

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    We present a thermo-mechanical stress analysis for five harness satin (5HS) woven carbon fiber reinforced polymer (CFRP) composite laminates with cracks under tension at cryogenic temperatures. The three-dimensional finite element model assumes the cracks to be located in the transverse fiber bundles and to span the thickness of the fiber bundles. Numerical calculations are carried out, and the Young's modulus and stress distributions near the crack fronts for two-layer and infinite-layer woven composite laminates are obtained and shown in graphical form. Results of this analysis demonstrate the effects of the residual thermal stresses and cracks on the mechanical behavior. (C) 2012 Elsevier Ltd. All rights reserved.

  161. Electromagneto-Mechanical Behavior of Giant Magnetostrictive/Piezoelectric Laminates in Three-Point Bending under Electric Fields 査読有り

    Y. Shindo, K. Mori, F. Narita, Y. Kori

    Advances in Theoretical and Applied Mechanics 5 (6) 291-307 2012年12月

  162. Dynamic electromagneto-mechanical behavior of clamped-free giant magnetostrictive/piezoelectric laminates under AC electric fields 査読有り

    Kotaro Mori, Yasuhide Shindo, Fumio Narita

    SMART MATERIALS AND STRUCTURES 21 (11) 115003 2012年11月

    出版者・発行元:IOP PUBLISHING LTD

    DOI: 10.1088/0964-1726/21/11/115003  

    ISSN:0964-1726

    eISSN:1361-665X

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    This work deals with the dynamic electromagneto-mechanical behavior of clamped-free giant magnetostrictive/piezoelectric laminates under AC electric fields both numerically and experimentally. The laminate is fabricated using thin magnetostrictive Terfenol-D and piezoelectric PZT layers. The magnetic field-dependent magnetoelastic constant and domain wall motion effect were incorporated to describe the nonlinear behavior of Terfenol-D and PZT layers, respectively, and three-dimensional finite element analysis was employed to calculate the displacement, stress and induced magnetic field. Experiments were also conducted to measure the displacement and induced magnetic field for the magnetostrictive/ piezoelectric laminates under AC electric fields. Comparison was then made between simulation and experiment.

  163. Modeling and Characterization of Strain Sensing in CNT-Based Polymer Composites under Tensile Loading 査読有り

    Y. Kuronuma, T. Takeda, Y. Shindo, F. Narita, Z. Wei

    Proceedings of the ASME 2012 International Mechanical Engineering Congress & Exposition 86474 (2 pages) 2012年11月

    DOI: 10.1115/IMECE2012-86474  

  164. Cryogenic Electromechanical Response of Multilayer PbZr_1-XTi_XO_3 Actuators under DC and AC Electric Fields in Hydrogen Fuel Injection Systems 招待有り 査読有り

    Y. Shindo, F. Narita

    ICCM2012 Proceedings 303 (7 pages) 2012年11月

  165. Dynamic fatigue behavior of cracked piezoelectric ceramics in three-point bending under AC electric fields 査読有り

    Fumio Narita, Yu Morikawa, Yasuhide Shindo, Masayuki Sato

    JOURNAL OF THE EUROPEAN CERAMIC SOCIETY 32 (14) 3759-3766 2012年11月

    出版者・発行元:ELSEVIER SCI LTD

    DOI: 10.1016/j.jeurceramsoc.2012.05.033  

    ISSN:0955-2219

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    This paper describes an experimental and analytical study on the dynamic fatigue behavior of cracked piezoelectric ceramics under AC electric fields. Constant load-rate testing was conducted in three-point bending with the single-edge precracked-beam specimens. The crack was created normal to the poling direction. The effects of AC electric fields and loading-rate on the fracture load were examined. A phenomenological model of domain wall motion was also used in finite element computation, and the energy release rate for the permeable crack model was calculated. The effect of AC electric fields on the critical energy release rate was then examined. The results suggest that (1) the fracture load of PZT ceramics decreases as the load-rate decreases; (2) an overall decrease in the fracture load occurs when testing under AC electric fields; and (3) the critical energy release rate is not very affected by the AC electric fields. (C) 2012 Elsevier Ltd. All rights reserved.

  166. Mechanical response of nonwoven polyester fabric/epoxy composites at cryogenic temperatures 査読有り

    Yasuhide Shindo, Tomo Takeda, Fumio Narita

    CRYOGENICS 52 (10) 564-568 2012年10月

    出版者・発行元:ELSEVIER SCI LTD

    DOI: 10.1016/j.cryogenics.2012.07.008  

    ISSN:0011-2275

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    In this work, we characterize the cryogenic mechanical response of nonwoven polyester/epoxy composites for high temperature superconducting devices. The test specimens were produced from the composite cylindrical components, and tension, compression and flexure tests were performed at room temperature and liquid nitrogen temperature (77 K) to evaluate the elastic and strength properties of the composites. The failure characteristics of the composites were examined by microscopic observations of failed specimens. The temperature dependence and anisotropy of the composite properties were discussed. (C) 2012 Elsevier Ltd. All rights reserved.

  167. Electrical resistance-based strain sensing in carbon nanotube/polymer composites under tension: Analytical modeling and experiments 査読有り

    Yu Kuronuma, Tomo Takeda, Yasuhide Shindo, Fumio Narita, Zhijuan Wei

    COMPOSITES SCIENCE AND TECHNOLOGY 72 (14) 1678-1682 2012年9月

    出版者・発行元:ELSEVIER SCI LTD

    DOI: 10.1016/j.compscitech.2012.07.001  

    ISSN:0266-3538

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    This paper presents an analytical and experimental study on the strain sensing behavior of carbon nanotube (CNT)-based polymer composites. Tensile tests were conducted on CNT/polycarbonate composites and the responses in the electrical resistance were measured during the tests. An analytical model incorporating the electrical tunneling effect due to the matrix material between CNTs was also developed to describe the electrical resistance change as a result of mechanical deformation. The model deals with the inter-nanotube matrix deformation at the micro/nanoscale due to the macroscale deformation of the nanocomposites. A comparison of the analytical predictions and the experimental data showed that the proposed model captures the sensing behavior. In addition, the effect of the micro/nanoscale structures on the strain induced resistance change was discussed to provide useful information for designing CNT-based polymer composites with high strain sensing capability. (c) 2012 Elsevier Ltd. All rights reserved.

  168. Relationship between Material Strength and Notched Failure of Woven Glass/Epoxy Composites under Fatigue Loading at Cryogenic Temperatures 査読有り

    Y. Shindo, T. Takeda, F. Narita

    Proceedings of Can’2012 Eleventh AES-ATEMA International Conference, Edited by Y. M. Haddad 221-225 2012年8月

  169. Static and Dynamic Fatigue of Cracked Piezoelectric Ceramics in Three-Point Bending under AC Electric Fields 査読有り

    Y. Shindo, F. Narita

    Proceedings of the 23rd International Congress of Theoretical and Applied Mechanics, Editors: Yilong Bai, Jianxiang Wang, Daining Fang SM05-014 (2 pages) 2012年8月

  170. Three-Dimensional Cryomechanics Analysis of Satin Woven Carbon/Polymer Composites with Cracks 査読有り

    F. Narita, Y. Shindo, T. Takeda

    Proceedings of the 23rd International Congress of Theoretical and Applied Mechanics, Editors: Yilong Bai, Jianxiang Wang, Daining Fang SM08-007 (2 pges) 2012年8月

  171. Dynamic Electromechanical Response of Multilayered Piezoelectric Composites from Room to Cryogenic Temperatures for Fuel Injector Applications 招待有り 査読有り

    Y. Shindo, T. Sasakura, F. Narita

    ASME Journal of Engineering Materials and Technology 134 (3) 031007 2012年7月

  172. Electromagneto-mechanical fields of giant magnetostrictive/piezoelectric laminates under concentrated load 査読有り

    Yasuhide Shindo, Yuzo Kori, Kotaro Mori, Fumio Narita

    International Journal of Smart and Nano Materials 3 (2) 169-182 2012年6月1日

    DOI: 10.1080/19475411.2011.649806  

    ISSN:1947-5411 1947-542X

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    This paper presents the nonlinear electromagneto-mechanical behavior of magnetostrictive/piezoelectric laminates under three-point bending both numerically and experimentally. The laminates are fabricated using thin Terfenol-D and PZT layers. The three-point bending test was conducted on the Terfenol-D/PZT laminates, and the displacement, induced magnetic field and induced voltage due to mechanical loads were measured. Three-dimensional finite element analysis was also carried out, and the electromagneto-mechanical fields in the laminates were predicted by introducing a second-order magnetoelastic constant for Terfenol-D. Comparison was then made between simulation and experiment. © 2012 Taylor &amp Francis.

  173. Dynamic Electromechanical Field Concentrations Near Electrodes in Piezoelectric Thick Films for the Design of MEMS Mirrors 査読有り

    Yasuhide Shindo, Fumio Narita, Koji Sato

    JOURNAL OF MECHANICAL DESIGN 134 (5) 051005 2012年5月

    出版者・発行元:ASME-AMER SOC MECHANICAL ENG

    DOI: 10.1115/1.4006265  

    ISSN:1050-0472

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    This paper studies the dynamic electromechanical response of piezoelectric mirrors driven by piezoelectric lead zirconate titanate (PZT) thick films both numerically and experimentally. The resonant frequency and the mirror tilt angle of piezoelectric mirrors under ac electric fields were analyzed by three-dimensional finite element method. The dynamic electromechanical field concentrations due to electrodes were also simulated and the results were discussed in detail. The mirrors consisted of four partially poled PZT unimorphs. The resonant frequency was then measured, and a comparison was made between the analysis and the experiment. The finite element method is shown to be capable of estimating the electromechanical field concentrations in the PZT films, making it a useful tool for designing future microelectromechanical systems (MEMS) mirrors. [DOI:10.1115/1.4006265]

  174. Static Fatigue of Three-Point Bending Piezoelectric Ceramics with a Single-Edge Crack Under AC Electric Fields 査読有り

    Yasuhide Shindo, Fumio Narita, Yu Morikawa

    JOURNAL OF THE AMERICAN CERAMIC SOCIETY 95 (4) 1326-1332 2012年4月

    出版者・発行元:WILEY-BLACKWELL

    DOI: 10.1111/j.1551-2916.2011.04949.x  

    ISSN:0002-7820

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    This article investigates experimentally and analytically the static fatigue behavior of cracked piezoelectric ceramics under ac electric fields. Static fatigue tests were carried out in three-point bending with the single-edge precracked-beam specimens. The crack was created normal to the poling direction. Time-to-failure under different mechanical loads and ac electric fields were obtained from the experiment. A phenomenological model of domain wall motion was also used in finite element computation, and the energy release rate for the permeable crack model was calculated. The effect of ac electric fields on the energy release rate versus lifetime curve was then examined.

  175. Electrical resistance change and crack behavior in carbon nanotube/polymer composites under tensile loading 招待有り 査読有り

    Yasuhide Shindo, Yu Kuronuma, Tomo Takeda, Fumio Narita, Shao-Yun Fu

    COMPOSITES PART B-ENGINEERING 43 (1) 39-43 2012年1月

    出版者・発行元:ELSEVIER SCI LTD

    DOI: 10.1016/j.compositesb.2011.04.028  

    ISSN:1359-8368

    eISSN:1879-1069

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    This paper studies the electrical and mechanical responses of cracked carbon nanotube (CNT)-based polymer composites. Tensile tests were performed on single-edge cracked plate specimens of the nanocomposites at room temperature and liquid nitrogen temperature (77 K), and the electrical resistance change of the specimens was monitored. An analytical model based on the electrical conduction mechanism of CNT-based composites was also developed to predict the resistance change resulted from crack propagation. The crack induced resistance change was calculated, and a comparison of the analytical predictions against the experimental data was made to validate the applicability of the model. In addition, the fracture properties of the nanocomposites were assessed in terms of the J-integrals using an elastic-plastic finite element analysis. (C) 2011 Elsevier Ltd. All rights reserved.

  176. Electromechanical Field Concentrations near Electrodes in Piezoelectric MEMS Mirrors 招待有り 査読有り

    Y. Shindo, F. Narita, K. Sato

    AES Technical Reviews Journals, PART C: International Journal of Advances and Trends in Engineering Materials and their Applications 1 (1) 81-86 2012年1月

  177. Crack growth characteristics of carbon nanotube-based polymer composites subjected to cyclic loading 査読有り

    Yu Kuronuma, Yasuhide Shindo, Tomo Takeda, Fumio Narita

    ENGINEERING FRACTURE MECHANICS 78 (17) 3102-3110 2011年12月

    出版者・発行元:PERGAMON-ELSEVIER SCIENCE LTD

    DOI: 10.1016/j.engfracmech.2011.09.006  

    ISSN:0013-7944

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    This paper presents the characterization of crack growth in carbon nanotube (CNT)-based polymer composites under fatigue loading. Fatigue crack growth tests were performed on single-edge cracked plate specimens of CNT/polycarbonate composites at room temperature and liquid nitrogen temperature (77 K). An elastic-plastic finite element analysis was also conducted to determine the J-integral range. The crack growth rate data were expressed in terms of the J-integral range, and the effect of nanotube addition on the fatigue crack growth behavior was examined. In addition, possible mechanisms of the crack growth in the nanocomposites are discussed based on microscopic observations of the specimen fracture surfaces. (C) 2011 Elsevier Ltd. All rights reserved.

  178. Electrical and Crack Responses of CNT-Based Polymer Composites under Tension 査読有り

    Y. Kuronuma, Y. Shindo, T. Takeda, F. Narita, S.-Y. Fu

    Proceedings of the ASME 2011 International Mechanical Engineering Congress & Exposition 62842 (2 pages) 2011年11月

  179. Cryogenic electromechanical behavior of multilayer piezo-actuators for fuel injector applications 査読有り

    Yasuhide Shindo, Fumio Narita, Takayoshi Sasakura

    JOURNAL OF APPLIED PHYSICS 110 (8) 084510 2011年10月

    出版者・発行元:AMER INST PHYSICS

    DOI: 10.1063/1.3656445  

    ISSN:0021-8979

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    This paper examines theoretically and experimentally the electromechanical behavior of multilayer piezo-actuators for fuel injectors at cryogenic temperatures. A thermodynamic model was employed to predict a monoclinic phase. A shift in the morphotropic phase boundary (MPB) between the tetragonal and rhombohedral/monoclinic phases with decreasing temperature was determined, and the temperature dependent piezoelectric coefficients were obtained. Temperature dependent coercive electric field was also predicted based on the domain wall energy. A finite element analysis was then performed to calculate the nonlinear electromechanical fields of the multilayer piezo-actuators from room to cryogenic temperatures, due to the shift in the MPB and polarization switching. In addition, experimental results on the electric field induced strain, which verify the model, were presented. (C) 2011 American Institute of Physics. [doi:10.1063/1.3656445]

  180. NONLINEAR ELECTROMECHANICAL FIELDS AND LOCALIZED POLARIZATION SWITCHING OF PIEZOELECTRIC MACROFIBER COMPOSITES 招待有り 査読有り

    Yasuhide Shindo, Fumio Narita, Koji Sato, Tomo Takeda

    JOURNAL OF MECHANICS OF MATERIALS AND STRUCTURES 6 (7-8) 1089-1102 2011年9月

    出版者・発行元:MATHEMATICAL SCIENCE PUBL

    DOI: 10.2140/jomms.2011.6.1089  

    ISSN:1559-3959

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    This paper examines theoretically and experimentally the nonlinear electromechanical response of piezoelectric macrofiber composites. 3D finite element analysis was carried out to study the strain versus electric field curve and the internal electromechanical fields near interdigitated electrodes in the macrofiber composites by introducing a model for polarization switching. The piezoelectric fibers in the macrofiber composite are partially or fully poled. Results on the strain versus electric field curves from micro-electromechanical models and simple experiments were also presented, and comparison was made with the finite element solutions.

  181. Modeling and characterization of the electrical conductivity of carbon nanotube-based polymer composites 査読有り

    Tomo Takeda, Yasuhide Shindo, Yu Kuronuma, Fumio Narita

    POLYMER 52 (17) 3852-3856 2011年8月

    出版者・発行元:ELSEVIER SCI LTD

    DOI: 10.1016/j.polymer.2011.06.046  

    ISSN:0032-3861

    eISSN:1873-2291

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    In this research, we investigate both analytically and experimentally the electrical properties of carbon nanotube (CNT)-based polymer composites. An analytical model was developed to predict the electrical conductivity of CNT-based composites. The micro/nanoscale structures of the nanocomposites and the electrical tunneling effect due to the matrix material between CNTs were incorporated within the model. Electrical conductivity measurements were also performed on CNT/polycarbonate composites to identify the dependence of their electrical transport characteristics on the nanotube content. The analytical predictions were compared with the experimental data, and a good correlation was obtained between the predicted and measured results. In addition, the effect of nanotube geometry on the nanocomposite electrical properties at the macroscale was examined. (C) 2011 Elsevier Ltd. All rights reserved.

  182. Vacuum crack growth behavior of austenitic stainless steel under fatigue loading 査読有り

    T. Takeda, Y. Shindo, F. Narita

    Strength of Materials 43 (5) 532-536 2011年8月

    DOI: 10.1007/s11223-011-9324-7  

    ISSN:0039-2316 1573-9325

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    The fatigue crack growth behavior of an austenitic stainless steel in a vacuum environment has been studied. Fatigue crack growth tests were performed with the compact tension specimens in laboratory air and vacuum, and the environmental effect on the crack growth behavior was examined. The crack growth rate data were expressed in terms of the J-integral range during fatigue loading, while an elastic-plastic finite element analysis was employed to calculate the J-integral range. The fractographic examinations were also carried out to assess the crack growth mechanisms and correlate with fatigue characteristics. The results show an accelerated fatigue crack growth in air compared to that in vacuum and this environmental effect depends on the load ratio. © 2011 Springer Science+Business Media, Inc.

  183. Effects of Electric Field and Poling on the Mode I Energy Release Rate for Two Symmetric Edge Cracks in Rectangular Piezoelectric Ceramic Strips 査読有り

    Y. Shindo, F. Narita, T. Matsuda

    Journal of Solid Mechanics and Materials Engineering 5 (7) 335-347 2011年7月

    出版者・発行元:The Japan Society of Mechanical Engineers

    DOI: 10.1299/jmmp.5.335  

    ISSN:1880-9871

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    This article discusses the results of the mode I energy release rate of rectangular piezoelectric ceramic strips with two symmetric edge cracks under electromechanical loading. Cracks were created normal or parallel to the poling direction, and applied electric fields were parallel/antiparallel to the poling. A nonlinear plane strain finite element analysis was performed, and the effect of localized polarization switching on the energy release rate was discussed for the permeable, impermeable, open and discharging cracks under a high negative electric field. In the case under a high positive electric field, we examined the effect of dielectric breakdown on the energy release rate.

  184. Electromagneto-Mechanical Behavior of Giant Magnetostrictive/Piezoelectric Laminates under Electric Fields for Self-Sensing Cantilever Actuators 査読有り

    K. Mori, Y. Shindo, F. Narita

    Journal of Solid Mechanics and Materials Engineering 5 (7) 360-369 2011年7月

    出版者・発行元:The Japan Society of Mechanical Engineers

    DOI: 10.1299/jmmp.5.360  

    ISSN:1880-9871

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    This work deals with the electromagneto-mechanical behavior of self-sensing giant magnetostrictive/piezoelectric laminated composites under electric fields both numerically and experimentally. The cantilever laminated composite is fabricated using thin magnetostrictive Terfenol-D and piezoelectric PZT layers. The magnetostriction of the laminated composite is first measured. Next, a nonlinear finite element analysis is performed to evaluate the second-order magnetoelastic constants in Terfenol-D layer bonded to PZT layer, using measured data. The tip deflection, internal stresses and induced magnetic field for the giant magnetostrictive/piezoelectric laminated composites under electric fields are then discussed in detail. Experimental results on the tip deflection and magnetic induction change due to electric fields, which verify the model, are also presented.

  185. Evaluation of Tensile Strength of Woven Carbon/Epoxy Composite Laminates at Cryogenic Temperatures Using the Open Hole Specimens 査読有り

    Shinya Watanabe, Yasuhide Shindo, Tomo Takeda, Fumio Narita, Satoru Yamaki

    JOURNAL OF TESTING AND EVALUATION 39 (4) 690-695 2011年7月

    出版者・発行元:AMER SOC TESTING MATERIALS

    DOI: 10.1520/JTE103132  

    ISSN:0090-3973

    eISSN:1945-7553

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    We propose a combined numerical-experimental method for the evaluation of the tensile strength properties of woven carbon fiber reinforced polymer (CFRP) composite laminates at cryogenic temperatures using the open hole specimens. Cryogenic tensile tests were conducted on the open hole specimens of quasi-isotropic woven CFRP laminates, and the length of the hole edge damage zone corresponding to the specimen failure was determined by the microscopic examinations of failed specimens. A finite element based method was developed for estimating the cryogenic tensile strength of the unnotched woven laminates using the experimentally determined failure load and damage zone length. In the damage zone, the material was assumed to carry a uniform normal stress equal to the tensile strength. The results demonstrate that the present method is an efficient approach to measuring the tensile strength of high-strength advanced composites at cryogenic temperatures.

  186. Electric field dependence of the mode I energy release rate in single-edge cracked piezoelectric ceramics: effect due to polarization switching/dielectric breakdown 査読有り

    Yasuhide Shindo, Fumio Narita, Takuya Matsuda

    ACTA MECHANICA 219 (1-2) 129-143 2011年6月

    出版者・発行元:SPRINGER WIEN

    DOI: 10.1007/s00707-011-0445-7  

    ISSN:0001-5970

    詳細を見る 詳細を閉じる

    This study presents the results of the mode I energy release rate of a rectangular piezoelectric material with a single-edge crack under electromechanical loading. A crack was created normal or parallel to the poling direction, and electric fields were applied parallel and antiparallel to the poling. A nonlinear plane strain finite element analysis was carried out, and the effect of localized polarization switching on the energy release rate was discussed for the permeable, impermeable, open, and discharging cracks under a high-negative electric field. The effect of dielectric breakdown on the energy release rate was also examined under a high-positive electric field.

  187. Electromechanical Response of Multilayer Piezoelectric Actuators for Fuel Injectors from Room to Cryogenic Temperatures 査読有り

    Y. Shindo, F. Narita, K. Sato, T. Sasakura

    Proceedings of the Third International Conference on Heterogeneous Material Mechanics, EDITORS Jinghong Fan, Junqian Zhang, Haibo Chen, Zhaohui Jin 295-502 2011年6月

  188. Evaluation of electromechanical properties and field concentrations near electrodes in piezoelectric thick films for MEMS mirrors by simulations and tests 査読有り

    Fumio Narita, Yasuhide Shindo, Koji Sato

    COMPUTERS & STRUCTURES 89 (11-12) 1077-1085 2011年6月

    出版者・発行元:PERGAMON-ELSEVIER SCIENCE LTD

    DOI: 10.1016/j.compstruc.2010.12.008  

    ISSN:0045-7949

    eISSN:1879-2243

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    We examine the nonlinear electromechanical response of piezoelectric mirrors driven by PZT thick films in a combined numerical and experimental investigation. First, some electromechanical tests were performed to measure the response (displacement versus load, displacement versus electric field) of the PZT thick films on elastic layers. A finite element analysis was then employed to determine the material properties in the PZT thick films using measured data. Next, the mirror tilt angle and electromechanical field concentrations due to electrodes in piezoelectric mirrors under electric fields were analyzed by introducing a model for polarization switching in local areas, and a nonlinear behavior was discussed in detail. The mirrors consisted of four fully or partially poled PZT unimorphs. Test results on the mirror tilt angle versus electric field, which verify the model, were also presented. (C) 2010 Elsevier Ltd. All rights reserved.

  189. Effect of Electric Field on the Response of Clamped-Free Magnetostrictive/Piezoelectric/Magnetostrictive Laminates 招待有り 査読有り

    K. Mori, F. Narita, Y. Shindo

    Computers, Materials & Continua 23 (3) 187-199 2011年5月

  190. Electromechanical Response of 1-3 Piezoelectric/Polymer Composites under DC and AC Electric Fields 招待有り 査読有り

    Y. Shindo, F. Narita, T. Watanabe

    AES Technical Reviews International Journals, Part D: International Journal of Reliability and Safety of Engineering Systems and Structures 1 (1) 23-30 2011年3月

  191. Cryogenic delamination growth in woven glass/epoxy composite laminates under mixed-mode I/II fatigue loading 査読有り

    Yasuhide Shindo, Masaya Miura, Tomo Takeda, Nozomi Saito, Fumio Narita

    COMPOSITES SCIENCE AND TECHNOLOGY 71 (5) 647-652 2011年3月

    出版者・発行元:ELSEVIER SCI LTD

    DOI: 10.1016/j.compscitech.2011.01.006  

    ISSN:0266-3538

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    This paper investigates the fatigue delamination growth behavior in woven glass fiber reinforced polymer (GFRP) composite laminates under mixed-mode I/II conditions at cryogenic temperatures. Fatigue delamination tests were performed with the mixed-mode bending (MMB) test apparatus at room temperature, liquid nitrogen temperature (77 K) and liquid helium temperature (4 K), in order to obtain the delamination growth rate as a function of the range of the energy release rate, and the dependence of the delamination growth behavior on the temperature and the mixed-mode ratio of mode I and mode II was examined. The energy release rate was evaluated using three-dimensional finite element analysis. The fractographic examinations by scanning electron microscopy (SEM) were also carried out to assess the mixed-mode fatigue delamination growth mechanisms in the woven GFRP laminates at cryogenic temperatures. (C) 2011 Elsevier Ltd. All rights reserved.

  192. Damage Development in Hybrid Composite Laminates under Three-point Bending at Cryogenic Temperatures 査読有り

    Masaya Miura, Yasuhide Shindo, Tomo Takeda, Fumio Narita

    ADVANCES IN FRACTURE AND DAMAGE MECHANICS IX 452-453 565-568 2011年

    出版者・発行元:TRANS TECH PUBLICATIONS LTD

    DOI: 10.4028/www.scientific.net/KEM.452-453.565  

    ISSN:1013-9826

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    This paper studies the damage behavior and interlaminar shear properties of hybrid composite laminates subjected to bending at cryogenic temperatures. Cryogenic short beam shear tests were performed on hybrid laminates combining woven glass fiber reinforced polymer (GFRP) composites with polyimide films, and microscopic observations of the specimens were made after the tests. A progressive damage analysis was also conducted to simulate the initiation and growth of damage in the specimens and to determine the interlaminar shear strength based on the maximum shear stress in the failure region. The predicted load-deflection curve and damage pattern show good agreement with the test results, and the numerically determined interlaminar shear strength is higher than the apparent interlaminar shear strength.

  193. NUMERICAL AND EXPERIMENTAL EVALUATION OF CRYOGENIC TENSILE STRENGTH OF WOVEN FABRIC-REINFORCED GLASS/EPOXY COMPOSITES USING OPEN HOLE SPECIMENS 招待有り 査読有り

    Yasuhide Shindo, Shinya Watanabe, Tomo Takeda, Fumio Narita, Takuya Matsuda, Satoru Yamaki

    JOURNAL OF MECHANICS OF MATERIALS AND STRUCTURES 6 (1-4) 545-556 2011年1月

    出版者・発行元:MATHEMATICAL SCIENCE PUBL

    DOI: 10.2140/jomms.2011.6.545  

    ISSN:1559-3959

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    A numerical and experimental evaluation of the tensile strength properties of woven glass fiber-reinforced polymer composite laminates at cryogenic temperatures was conducted by means of open hole specimens. Tensile tests were performed on specimens with a circular hole at room temperature, at 77 K, and at 4 K. The length of the hole edge damage zone corresponding to specimen failure was determined by microscopic examination of the fracture surfaces. A method based on finite element analysis was developed for estimating the cryogenic tensile strength of the unnotched woven laminates using the experimentally determined failure load and damage zone length. The results suggest that the tensile strength of woven composite laminates at cryogenic temperatures can be determined effectively by this approach.

  194. Electromechanical Filed Concentrations and Polarization Switching Due to Interdigitated Electrodes in Piezoelectric Macro-Fiber Composites under Tension 査読有り

    Fumio Narita, Yasuhide Shindo, Koji Sato, Tomo Takeda

    BEHAVIOR AND MECHANICS OF MULTIFUNCTIONAL MATERIALS AND COMPOSITES 2011 7978 79781T-1-79781T-6 2011年

    出版者・発行元:SPIE-INT SOC OPTICAL ENGINEERING

    DOI: 10.1117/12.880044  

    ISSN:0277-786X

    詳細を見る 詳細を閉じる

    This work investigates the electromechanical response of piezoelectric macro-fiber composites (MFCs) under tension. Nonlinear three dimensional finite element model incorporating the polarization switching mechanism was used to predict the electromechanical fields near interdigitated electrode (IDEs) in the piezoelectric MFCs. The lead zirconate titanate (PZT) fibers in the MFC are partially poled. The electric field-induced strain was then measured, and test results were presented to validate the predictions.

  195. Effect of damage on the interlaminar shear properties of hybrid composite laminates at cryogenic temperatures 査読有り

    Masaya Miura, Yasuhide Shindo, Tomo Takeda, Fumio Narita

    COMPOSITE STRUCTURES 93 (1) 124-131 2010年12月

    出版者・発行元:ELSEVIER SCI LTD

    DOI: 10.1016/j.compstruct.2010.06.008  

    ISSN:0263-8223

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    This paper presents the experimental and numerical characterization of the interlaminar shear failure of hybrid composite laminates at cryogenic temperatures. Cryogenic short beam shear tests were performed on hybrid laminates consisting of woven glass fiber reinforced polymer (GFRP) composites and polyimide films to evaluate their interlaminar shear strength. Microscopic observations of damage accumulation and failure mechanisms were also made on failed specimens. In addition, a progressive damage analysis was conducted to predict the initiation and growth of damage in the specimens, and the interlaminar shear strength was determined from the maximum shear stress in the failure region. The damage effect on the interlaminar shear properties of hybrid laminates at cryogenic temperatures was examined based on the experimental and numerical results. (C) 2010 Elsevier Ltd. All rights reserved.

  196. Tensile and Compressive Behavior of Multi-Walled Carbon Nanotube/Polymer Composites 査読有り

    T. Takeda, Y. Kuronuma, Y. Shindo, F. Narita

    Proceedings of the Second Asian Conference on Mechanics of Functional Materials and Structures, Edited by Cun-Fa Gao and Yong-Jian Wang 425-528 2010年10月

  197. Tensile Strength Determination for Woven Glass/Epoxy Composite Laminates at Cryogenic Temperatures Using the Open Hole Specimens 査読有り

    Y. Shindo, S. Watanabe, T. Takeda, F. Narita, T. Matsuda, S. Yamaki

    Proceedings of the Ninth China-Japan Joint Conference on Composite Materials, Edited by Qingqing Ni, Jiang Liu 67-70 2010年9月

  198. Cryomechanics of Structural Alloys for Superconducting Device Applications 査読有り

    Y. Shindo, T. Takeda, F. Narita

    AES Technical Reviews Journals, Part B: International Journal of Advances in Mechanics and Applications of Industrial Materials 1 (1) 41-47 2010年8月

  199. Dynamic characteristics and electromechanical fields of 1-3 piezoelectric/polymer composites under AC electric fields 査読有り

    Fumio Narita, Yasuhide Shindo, Taiki Watanabe

    SMART MATERIALS & STRUCTURES 19 (7) 075004 2010年7月

    出版者・発行元:IOP PUBLISHING LTD

    DOI: 10.1088/0964-1726/19/7/075004  

    ISSN:0964-1726

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    This paper studies the dynamic electromechanical response of 1-3 piezoelectric/polymer composites under alternating current (AC) electric fields. The piezocomposites contain square or circular piezoelectric rods in an epoxy matrix. Experiments were conducted to measure the electrical impedance and phase angle at various frequencies, using the device specimen of the 1-3 piezocomposites. Three dimensional finite element analysis was also employed to calculate the frequency characteristics, and a comparison is made between simulation and experiment. The dynamic electromechanical fields in the 1-3 piezocomposites are then discussed in detail.

  200. Nonlinear electromechanical fields and localized polarization switching of 1-3 piezoelectric/polymer composites 査読有り

    Yasuhide Shindo, Fumio Narita, Taiki Watanabe

    EUROPEAN JOURNAL OF MECHANICS A-SOLIDS 29 (4) 647-653 2010年7月

    出版者・発行元:GAUTHIER-VILLARS/EDITIONS ELSEVIER

    DOI: 10.1016/j.euromechsol.2010.03.009  

    ISSN:0997-7538

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    This paper examines the nonlinear electromechanical response of 1-3 piezoelectric/polymer composites. The piezocomposites contain square or circular piezoelectric rods in an epoxy matrix. Experiments were conducted to measure the displacement versus electric field curves, using the device specimen of the 1-3 piezocomposites. Three dimensional finite element analysis was also carried out to study the electromechanical fields in the 1-3 piezocomposites by introducing a model for polarization switching. Comparison was then made between simulation and experiment. (c) 2010 Elsevier Masson SAS. All rights reserved.

  201. Electromagneto-mechanical fields of giant magnetostrictive/piezoelectric laminates 査読有り

    Yasuhide Shindo, Kotaro Mori, Fumio Narita

    ACTA MECHANICA 212 (3-4) 253-261 2010年7月

    出版者・発行元:SPRINGER WIEN

    DOI: 10.1007/s00707-009-0259-z  

    ISSN:0001-5970

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    This paper presents the nonlinear electromagneto-mechanical behavior of magnetostrictive/piezoelectric laminated pieces under magnetic fields both numerically and experimentally. The pieces are fabricated using thin Tb(0.3)Dy(0.7)Fe(2) (Terfenol-D) and Pb(Zr,Ti)O(3) (PZT) layers, and the magnetostriction of the pieces is measured. A nonlinear finite element analysis is also employed to evaluate the second-order magnetoelastic constants in Terfenol-D layer bonded to the PZT layer, and the nonlinear displacement, internal stresses and induced voltage for the magnetostrictive/piezoelectric laminated pieces under magnetic fields are discussed.

  202. Singular Stress Fields for Transverse Cracks in Multi-Layer Satin Woven CFRP Composite Laminates under Cryogenic Conditions 査読有り

    S. Watanabe, Y. Shindo, T. Takeda, F. Narita

    Advances in Theoretical and Applied Mechanics 3 (8) 349-367 2010年7月

  203. Progressive Damage Response of Hybrid Composite Laminates under Three-Point Short Beam Shear Loading at Cryogenic Temperatures 査読有り

    M. Miura, Y. Shindo, T. Takeda, F. Narita

    Proceedings of the 16th US National Congress of Theoretical and Applied Mechanics 755 (2 pages) 2010年7月

  204. Fatigue Crack Growth Behavior of CNT-Based Polymer Composites 査読有り

    Y. Kuronuma, Y. Shindo, T. Takeda, F. Narita

    Multiscaling of Synthetic and Natural Systems with Self-Adaptive Capability, Editors: G. C. Sih and C. K. Chao 117-120 2010年6月

  205. Effect of Electric Field on the Bending Response of Magnetostrictive/Piezoelectric Laminated Composites 査読有り

    K. Mori, F. Narita, Y. Shindo

    ACMA 2010 Abstracts and CD-ROM Proceedings, Editors: M. Karama, A. Menou, A. Moudden and A. El Hami 34 (6pages) 2010年5月

  206. Electric Delayed Fracture and Localized Polarization Switching of Cracked Piezoelectric Ceramics in Three-point Bending 査読有り

    Fumio Narita, Yasuhide Shindo, Mitsuru Hirama

    INTERNATIONAL JOURNAL OF DAMAGE MECHANICS 19 (3) 285-300 2010年4月

    出版者・発行元:SAGE PUBLICATIONS LTD

    DOI: 10.1177/1056789509103642  

    ISSN:1056-7895

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    This article discusses the delayed fracture and localized polarization switching near a crack tip in three-point bending piezoceramics under electromechanical loading. We have used finite element analysis to study delayed fracture experiments with single-edge precracked-beam method. A nonlinear finite element analysis was employed to calculate the fracture mechanics parameters such as energy release rate for the permeable, impermeable, and open crack face boundary conditions. Recent proposed energetically consistent boundary conditions were also considered. The effects of applied electric field and localized polarization switching on the fracture mechanics parameters were then examined.

  207. CRYOGENIC FRACTURE BEHAVIOR OF METASTABLE AUSTENITIC STAINLESS STEEL IN A HIGH MAGNETIC FIELD 査読有り

    Y. Shindo, F. Narita, M. Suzuki, I. Shindo

    STRENGTH OF MATERIALS 42 (2) 221-225 2010年3月

    出版者・発行元:SPRINGER

    DOI: 10.1007/s11223-010-9210-8  

    ISSN:0039-2316

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    We study the effect of magnetic field on the fracture behavior of the metastable austenitic stainless steels at cryogenic temperatures. Elastic-plastic fracture toughness tests were performed on compact tension specimens in liquid helium at 4 K with and without a magnetic field, and the effect of magnetic field on the cryogenic fracture toughness was discussed. Quantitative phase analysis was also done by magnetic method, and the fracture surfaces were examined by scanning electron microscopy to correlate with the fracture properties.

  208. Magnetic Field on Stress Intensification in Soft Ferromagnetic Materials 査読有り

    Y. Shindo, I. Shindo, F. Narita

    Particle and Continuum Aspects of Mesomechanics 739-747 2010年2月4日

    出版者・発行元:wiley

    DOI: 10.1002/9780470610794.ch76  

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    The purpose of this paper is to investigate the effect of magnetic fields on the fracture toughness of nickel iron soft ferromagnetic materials. Tensile tests were performed using single-edge cracked plate specimens in a magnetic filed, and the critical load was measured. The magnetoelastic analysis of a soft ferromagnetic strip with a single-edge crack was also done to calculate the magnetic stress intensity factor, and the fracture toughness was obtained using critical load.

  209. Fracture behaviour of cracked carbon nanotube-based polymer composites: Experiments and finite element simulations 査読有り

    Y. Kuronuma, Y. Shindo, T. Takeda, F. Narita

    FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES 33 (2) 87-93 2010年2月

    出版者・発行元:WILEY-BLACKWELL PUBLISHING, INC

    DOI: 10.1111/j.1460-2695.2009.01419.x  

    ISSN:8756-758X

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    This paper studies the fracture behaviour of cracked carbon nanotube (CNT)-based polymer composites by a combined numerical-experimental approach. Tensile tests were conducted on single-edge cracked plate specimens of CNT/polycarbonate composites at room temperature and liquid nitrogen temperature (77 K), and the critical loads for fracture instabilities were determined. Elastic-plastic finite element simulations of the tests were then performed to evaluate the J-integrals corresponding to the experimentally determined critical loads. Scanning electron microscopy examinations were also made on the specimen fracture surfaces, and the fracture mechanisms of the CNT-based composites were discussed.

  210. T0101-5-3 き裂を有するカーボンナノチューブ分散ポリマーコンポジットの破壊挙動([T0101-5]マイクロ・ナノ材料システムの力学と強度・機能評価(5))

    黒沼 遊, 進藤 裕英, 竹田 智, 成田 史生

    年次大会講演論文集 2010 51-52 2010年

    出版者・発行元:一般社団法人日本機械学会

    DOI: 10.1299/jsmemecjo.2010.8.0_51  

    詳細を見る 詳細を閉じる

    This paper studies the fracture behavior of carbon nanotube (CNT)-based polymer composites by a combined numerical-experimental approach. Tensile tests were conducted on single-edge cracked plate specimens of CNT/polycarbonate composites at room temperature and liquid nitrogen temperature (77 K), and the critical loads for fracture instabilities were determined. Elastic-plastic finite element simulations of the tests were then performed to evaluate the J-integrals corresponding to the experimentally determined critical loads. Scanning electron microscopy (SEM) examinations were also made on the specimen fracture surfaces, and the fracture mechanisms of the CNT-based composites were discussed.

  211. T0101-2-3 電磁場下における超磁歪/圧電積層デバイスの感知・応答特性([T0101-2]マイクロ・ナノ材料システムの力学と強度・機能評価(2):スマート材料システムの強度・機能評価)

    成田 史生, 森 孝太郎, 進藤 裕英

    年次大会講演論文集 2010 17-18 2010年

    出版者・発行元:一般社団法人日本機械学会

    DOI: 10.1299/jsmemecjo.2010.8.0_17  

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    This work presents the nonlinear bending response of magnetostrictive/piezoelectric laminated devices under electromagnetic fields both numerically and experimentally. The devices are fabricated using thin Terfenol-D and PZT layers. The magnetostriction of the Terfenol-D layer bonded to the PZT layer is measured, and a nonlinear finite element analysis is performed to evaluate the second-order magnetoelastic constants in Terfenol-D layer using measured data. The deflection, internal stresses and induced voltage/magnetic field for the laminated devices under magnetic/electric fields are then discussed in detail.

  212. Bending Response of Carbon Nanotube-Based Polymer Composites at Cryogenic Temperatures 査読有り

    Y. Kuronuma, Y. Shindo, Y. Mito, T. Takeda, F. Narita

    Advances in Cryogenic Engineering 56 47-54 2010年

    DOI: 10.1063/1.3402332  

  213. Interlaminar shear properties of composite insulation systems for fusion magnets at cryogenic temperatures 査読有り

    Yasuhide Shindo, Tomo Takeda, Fumio Narita, Masaya Miura, Shinya Watanabe, Norikiyo Koizumi, Akira Idesaki, Kiyoshi Okuno

    CRYOGENICS 50 (1) 36-42 2010年1月

    出版者・発行元:ELSEVIER SCI LTD

    DOI: 10.1016/j.cryogenics.2009.10.006  

    ISSN:0011-2275

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    This paper reports the cryogenic interlaminar shear properties of composite insulation systems for the superconducting magnet coils in the International Thermonuclear Experimental Reactor (ITER). Short beam shear tests were performed at room temperature, liquid nitrogen temperature (77 K) and liquid helium temperature (4 K) on three insulation systems consisting of woven glass fiber reinforced plastic (GFRP) composites with different polymer resins and polyimide films, and the dependence of their apparent interlaminar shear strength on the temperature and the polymer resins was discussed. A detailed observation of failed specimens was made to verify the failure mechanisms. Insulation systems subjected to gamma irradiation at room temperature were also considered, and the effect of irradiation on the cryogenic interlaminar shear properties was examined. (C) 2009 Elsevier Ltd. All rights reserved.

  214. Bending Response of Carbon Nanotube-based Polymer Composites at Cryogenic Temperatures 査読有り

    Y. Kuronuma, Y. Shindo, Y. Mito, T. Takeda, F. Narita

    Advances in Cryogenic Engineering 56 47-54 2010年1月

    DOI: 10.1063/1.3402332  

  215. Nonlinear bending response of Terfenol-D/PZT laminated devices under electromagnetic fields 査読有り

    Kotaro Mori, Fumio Narita, Yasuhide Shindo

    BEHAVIOR AND MECHANICS OF MULTIFUNCTIONAL MATERIALS AND COMPOSITES 2010 7644 764424-1-764424-8 2010年

    出版者・発行元:SPIE-INT SOC OPTICAL ENGINEERING

    DOI: 10.1117/12.846400  

    ISSN:0277-786X

    詳細を見る 詳細を閉じる

    This work presents the nonlinear bending response of magnetostrictive/piezoelectric laminated devices under electromagnetic fields both numerically and experimentally. The devices are fabricated using thin Terfenol-D and PZT layers. The magnetostriction of the Terfenol-D layer bonded to the PZT layer is measured, and a nonlinear finite element analysis is performed to evaluate the second-order magnetoelastic constants in Terfenol-D layer using measured data. The deflection, internal stresses and induced voltage/magnetic field for the laminated devices under magnetic/electric fields are then discussed in detail.

  216. Fatigue Crack Propagation in Three-Point Bending Piezoceramics under Electromechanical Loading 招待有り 査読有り

    Y. Shindo, F. Narita, M. Hirama

    AES Technical Reviews Journals, Part B: International Journal of Advances in Mechanics and Applications of Industrial Materials 1 (1) 11-21 2009年10月

  217. Delamination growth mechanisms in woven glass fiber reinforced polymer composites under Mode II fatigue loading at cryogenic temperatures 査読有り

    Yasuhide Shindo, Tomo Takeda, Fumio Narita, Nozomi Saito, Shinya Watanabe, Kazuaki Sanada

    COMPOSITES SCIENCE AND TECHNOLOGY 69 (11-12) 1904-1911 2009年9月

    出版者・発行元:ELSEVIER SCI LTD

    DOI: 10.1016/j.compscitech.2009.04.010  

    ISSN:0266-3538

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    The purpose of this research is to characterize the cryogenic delamination growth behavior in woven glass fiber reinforced polymer (GFRP) composite laminates subjected to Mode II fatigue loading. Mode II fatigue delamination tests were performed at room temperature, liquid nitrogen temperature (77 K) and liquid helium temperature (4 K) using the four-point bend end-notched flexure (4ENF) test method, and the delamination growth rate data for the woven GFRP laminates were obtained. The energy release rate range was determined by the finite element method. Microscopic examinations of the specimen sections and fracture surfaces were also carried out. The present results are discussed to obtain an understanding of the fatigue delamination growth mechanisms in the woven GFRP laminates under Mode II loading at cryogenic temperatures. (C) 2009 Elsevier Ltd. All rights reserved.

  218. Electromechanical field concentrations near the electrode tip in partially poled multilayer piezo-film actuators 査読有り

    Yasuhide Shindo, Fumio Narita, Mitsuru Hirama

    SMART MATERIALS & STRUCTURES 18 (8) 085020 2009年8月

    出版者・発行元:IOP PUBLISHING LTD

    DOI: 10.1088/0964-1726/18/8/085020  

    ISSN:0964-1726

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    This paper describes the results of our numerical and experimental studies of the electromechanical field concentrations due to electrodes in partially poled multilayer piezoelectric film actuators under electric fields. A nonlinear finite element analysis is performed to create the partial poling state through the high electric field and to discuss the electromechanical fields. Displacement versus electric field curves are also measured to validate the numerical predictions, and comparisons are made between numerical results and experimental data. Moreover, the results of the partially poled multilayer actuators are compared with those of fully poled actuators.

  219. Fatigue Crack Growth Behavior of Metastable Austenitic Stainless Steel in Cryogenic High Magnetic Field Environments 査読有り

    Yasuhide Shindo, Tomo Takeda, Masato Suzuki, Fumio Narita

    METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE 40A (8) 1863-1867 2009年8月

    出版者・発行元:SPRINGER

    DOI: 10.1007/s11661-009-9876-3  

    ISSN:1073-5623

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    This article studies the fatigue crack growth in a metastable austenitic stainless steel in cryogenic high magnetic field environments. Fatigue crack growth tests were performed with the compact tension (CT) specimens at liquid helium temperature (4 K) in magnetic fields of 0 and 6 T, and the crack growth rate data were expressed in terms of the J-integral range during fatigue loading. The J-integral range values were evaluated using an elastic-plastic finite element analysis. The measurement of martensite phase in the test specimens and the fractographic examination were also carried out. The high magnetic field effect on the fatigue crack growth rate properties at 4 K is discussed in detail.

  220. Mode III fatigue delamination growth of glass fiber reinforced polymer woven laminates at cryogenic temperatures 査読有り

    Masaya Miura, Yasuhide Shindo, Fumio Narita, Shinya Watanabe, Masato Suzuki

    CRYOGENICS 49 (8) 407-412 2009年8月

    出版者・発行元:ELSEVIER SCI LTD

    DOI: 10.1016/j.cryogenics.2009.05.004  

    ISSN:0011-2275

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    This paper investigates the cryogenic fatigue delamination behavior of glass fiber reinforced polymer woven laminates under Mode III loading. Fatigue delamination tests were conducted using split cantilever beam specimens at room temperature, liquid nitrogen temperature (77 K) and liquid helium temperature (4 K). A finite element analysis was also employed to calculate the energy release rate. The temperature dependence of the fatigue delamination growth rate vs. energy release rate range is discussed. Fracture surfaces were examined by scanning electron microscopy to identify the delamination mechanisms under fatigue loading. The important conclusion we reach is that the Mode III fatigue delamination growth rates of woven laminates at cryogenic temperatures are lower than that at room temperature. (C) 2009 Elsevier Ltd. All rights reserved.

  221. Mode I Energy Release Rate in Cracked Piezoelectric Ceramics under Electric Fields 査読有り

    Y. Shindo, F. Narita

    Proceedings of AES-TEMA’2009 International Conference 35-41 2009年7月

  222. Cryomechanics of Structural Alloys for Superconducting Device Applications 招待有り 査読有り

    Y. Shindo, T. Takeda, F. Narita

    Proceedings of AES-TEMA’2009 International Conference 319-320 2009年7月

  223. Delayed Fracture of Cracked Piezoelectric Ceramics under Electromechanical Loading in Three-Point Bending 査読有り

    Y. Shindo, F. Narita, M. Hirama

    Proceedings, The 12th International Conference on Fracture T42.011 2009年7月

  224. Thermal-mechanical Analysis of Satin Weave CFRP Composites with Cracks at Cryogenic Temperatures 査読有り

    Shinya Watanabe, Yasuhide Shindo, Fumio Narita, Tomo Takeda

    JOURNAL OF REINFORCED PLASTICS AND COMPOSITES 28 (11) 1319-1337 2009年6月

    出版者・発行元:SAGE PUBLICATIONS LTD

    DOI: 10.1177/0731684408089133  

    ISSN:0731-6844

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    This study deals with the thermal-mechanical behavior of satin weave carbon fiber-reinforced polymer (CFRP) laminates with internal and/or edge cracks and temperature-dependent material properties under tension at cryogenic temperatures. Cracks are assumed to be located in the transverse fiber bundles and extend to the interfaces between two fiber bundles. Young&apos;s modulus and stress distributions near the crack tip under combined mechanical and thermal loads are predicted by finite element models that assume generalized plane strain. The effects of residual thermal stresses and cracks on the mechanical behavior of CFRP woven laminates at cryogenic temperatures are calculated, and the numerical results are presented in graphical form.

  225. NONLINEAR BENDING RESPONSE OF GIANT MAGNETOSTRICTIVE LAMINATED ACTUATORS IN MAGNETIC FIELDS 招待有り 査読有り

    Yasuhide Shindo, Fumio Narita, Kotaro Mori, Tasuku Nakamura

    JOURNAL OF MECHANICS OF MATERIALS AND STRUCTURES 4 (5) 941-949 2009年5月

    出版者・発行元:MATHEMATICAL SCIENCE PUBL

    DOI: 10.2140/jomms.2009.4.941  

    ISSN:1559-3959

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    We report numerical and experimental investigations into the nonlinear bending behavior of magnetostrictive laminated actuators under magnetic fields. Magnetostrictive actuators were fabricated from thin layers of Terfenol-D and metal, and the magnetostriction of the devices was measured. A nonlinear finite element analysis was employed to evaluate the contribution of magnetic domain switching to the second-order magnetoelastic constants in the Terfenol-D layer. The effect of a magnetic field on the nonlinear deflection and internal stress of magnetostrictive laminated actuators is discussed.

  226. DYNAMIC FATIGUE OF CRACKED PIEZOELECTRIC CERAMICS UNDER ELECTROMECHANICAL LOADING: THREE-POINT BENDING TEST AND FINITE ELEMENT ANALYSIS 査読有り

    Yasuhide Shindo, Fumio Narita, Mitsuru Hirama

    JOURNAL OF MECHANICS OF MATERIALS AND STRUCTURES 4 (4) 719-729 2009年4月

    出版者・発行元:MATHEMATICAL SCIENCE PUBL

    DOI: 10.2140/jomms.2009.4.719  

    ISSN:1559-3959

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    This paper studies the dynamic fatigue or slow crack growth in piezoelectric ceramics under electromechanical loading by a combined numerical-experimental approach. Constant load-rate testing was conducted in three-point flexure using the single-edge precracked-beam specimens under zero and positive electric fields, and the effects of electric field and loading-rate on the fracture load and crack propagation were examined. A finite element analysis was also employed to calculate the energy release rate for the permeable, impermeable and open crack models, and the effect of electric field on the energy release rate was discussed. Crack propagation velocity versus energy release rate curves at various loading-rate were then estimated based on the finite element analysis using measured data.

  227. Tensile Characterization of Carbon Nanotube-Reinforced Polymer Composites at Cryogenic Temperatures: Experimens and Multiscale Simulations 査読有り

    Tomo Takeda, Yasuhide Shindo, Furnio Narita, Yuya Mito

    MATERIALS TRANSACTIONS 50 (3) 436-445 2009年3月

    出版者・発行元:JAPAN INST METALS

    DOI: 10.2320/matertrans.MBW200817  

    ISSN:1345-9678

    eISSN:1347-5320

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    The purpose of this research is to experimentally and numerically evaluate the mechanical performance of carbon nanotube (CNT)-reinforced polymer composites subjected to tension in a cryogenic environment. Cryogenic tensile tests were conducted on CNT/polycarbonate composites to identify the effects of CNTs on their tensile properties. Finite element computations were also conducted using a model for the representative volume element (RVE) of CNT-reinforced composites in order to determine the effective composite elastic modulus and the stress state within the composites. The possible existence of the imperfect interface bonding between the CNT and the matrix was considered in the finite element model. The CNT properties used in the analysis were obtained by employing an analytical molecular structural mechanics model. The numerical findings were then correlated with the experimental results. [doi: 10.2320/matertrans.MBW200817]

  228. Effect of the electrical boundary condition at the crack face on the mode I energy release rate in piezoelectric ceramics 査読有り

    Yasuhide Shindo, Fumio Narita, Mitsuru Hirama

    APPLIED PHYSICS LETTERS 94 (8) 081902 2009年2月

    出版者・発行元:AMER INST PHYSICS

    DOI: 10.1063/1.3088855  

    ISSN:0003-6951

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    This paper discusses the crack behavior of rectangular piezoelectric ceramics under electromechanical loading. A finite element analysis was employed to calculate the fracture mechanics parameters such as mode I energy release rate for the permeable, impermeable, and open crack models. Recently proposed nonlinear electrically discharging crack model was also considered. The effect of applied electric fields on the fracture mechanics parameters was then examined under various electrical boundary conditions at the crack face.

  229. T0101-3-1 超磁歪/圧電積層デバイスの電磁力学場(機能材料)

    森 孝太郎, 成田 史生, 進藤 裕英

    年次大会講演論文集 2009 21-22 2009年

    出版者・発行元:一般社団法人日本機械学会

    DOI: 10.1299/jsmemecjo.2009.8.0_21  

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    This paper presents the nonlinear electromagneto-mechanical behavior of magnetostrictive/piezoelectric laminated sensors and actuators under magnetic fields both numerically and experimentally. The devices are fabricated using thin Terfenol-D and PZT layers, and the magnetostriction of the devices is measured. A nonlinear finite element analysis is also employed to evaluate the contribution of magnetic domain switching to the second-order magnetoelastic constants in Terfenol-D layer bonded to the PZT layer, and the nonlinear displacement, internal stresses and induced voltage for the magnetostrictive/piezoelectric laminated devices under magnetic fields are discussed.

  230. T0101-2-5 1-3圧電/ポリマーコンポジットの非線形電気力学場と局所分極回転(複合材料2)

    渡邉 大樹, 進藤 裕英, 成田 史生

    年次大会講演論文集 2009 19-20 2009年

    出版者・発行元:一般社団法人日本機械学会

    DOI: 10.1299/jsmemecjo.2009.8.0_19  

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    This work deals with the nonlinear electromechanical response of 1-3 piezocomposites. The composites contain square or circular piezoelectric rods in an epoxy matrix. Experiments were performed to measure the displacement versus electric field curves. Three dimensional finite element analysis was also conducted to study the electromechanical fields in the 1-3 piezocomposites by introducing a model for polarization switching. Comparison was then made between numerical results and experimental data.

  231. Dynamic Electromechanical Response and Self-Sensing of Functionally Graded Piezoelectric Cantilever Transducers 査読有り

    Yasuhide Shindo, Fumio Narita, Jun Nakagawa

    JOURNAL OF INTELLIGENT MATERIAL SYSTEMS AND STRUCTURES 20 (1) 119-126 2009年1月

    出版者・発行元:SAGE PUBLICATIONS LTD

    DOI: 10.1177/1045389X08090115  

    ISSN:1045-389X

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    This article studies the activity and sensitivity of functionally graded piezoelectric cantilever transducers under electromechanical loading through numerical and experimental characterizations. A phenomenological model of domain wall motion in alternating current (AC) electric fields is used, and a nonlinear 3D finite element method is employed to simulate the dynamic response of functionally graded piezoelectric cantilever transducers. The effects of AC electric field amplitude and frequency, number of layers, and property gradation on the output voltage, deflection and internal stresses of the transducers are examined. Experimental results, which verify the model, are also presented using functionally graded piezoelectric bimorphs.

  232. Cryogenic Behavior of Cracks in Satin Woven CFRP Laminates under Tensile Loading 査読有り

    S. Watanabe, Y. Shindo, T. Takeda, F. Narita, K. Sanada

    JSME Journal of Solid Mechanics and Materials Engineering 3 (1) 22-37 2009年1月

    出版者・発行元:The Japan Society of Mechanical Engineers

    DOI: 10.1299/jmmp.3.22  

    ISSN:1880-9871

    詳細を見る 詳細を閉じる

    The objective of this research is to investigate the crack behavior in five harness satin woven carbon fiber reinforced polymer (CFRP) composite laminates with temperature-dependent material properties under tension at cryogenic temperatures. A situation of generalized plane strain is considered, and cracks are assumed to have occurred in the transverse fiber bundles. Also, both cases where the tips of the cracks are located in the fiber bundles or at the interfaces between two fiber bundles are treated, and a finite element technique utilizing special singular elements is used to obtain the stress intensity factors at the tips of the transverse cracks in two-layer woven CFRP laminates. The numerical results are then discussed in detail.

  233. Effect of magnetic field on the bending response of magnetostrictive/ piezoelectric laminated actuators 査読有り

    Fumio Narita, Yasuhide Shindo, Kotaro Mori

    Proceedings of SPIE - The International Society for Optical Engineering 7289 72891V 2009年

    DOI: 10.1117/12.815275  

    ISSN:0277-786X

    詳細を見る 詳細を閉じる

    This work presents the nonlinear bending response of magnetostrictive/ piezoelectric laminated actuators under magnetic fields both numerically and experimentally. The actuators are fabricated using thin Terfenol-D and PZT layers, and the magnetostriction of the actuators is measured. A nonlinear finite element analysis is also performed to evaluate the contribution of magnetic domain switching to the second-order magnetoelastic constants in Terfenol-D layer, and the effect of magnetic field on the deflection, internal stresses and induced voltage for the magnetostrictive/piezoelectric laminated actuators are discussed in detail. © 2009 SPIE.

  234. Electroelastic Wave Scattering in a Cracked Dielectric Polymer under a Uniform Electric Field 査読有り

    Yasuhide Shindo, Fumio Narita

    BOUNDARY VALUE PROBLEMS 2009 949124 2009年

    出版者・発行元:SPRINGER INTERNATIONAL PUBLISHING AG

    DOI: 10.1155/2009/949124  

    ISSN:1687-2770

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    We investigate the scattering of plane harmonic compression and shear waves by a Griffith crack in an infinite isotropic dielectric polymer. The dielectric polymer is permeated by a uniform electric field normal to the crack face, and the incoming wave is applied in an arbitrary direction. By the use of Fourier transforms, we reduce the problem to that of solving two simultaneous dual integral equations. The solution of the dual integral equations is then expressed in terms of a pair of coupled Fredholm integral equations of the second kind having the kernel that is a finite integral. The dynamic stress intensity factor and energy release rate for mode I and mode II are computed for different wave frequencies and angles of incidence, and the influence of the electric field on the normalized values is displayed graphically. Copyright (C) 2009 Y. Shindo and F. Narita.

  235. Nonlinear Dynamic Bending and Self-sensing of Clamped-Clamped Functionally Graded Piezoelectric Transducers under AC Voltage 招待有り 査読有り

    Yasuhide Shindo, Fumio Narita, Jun Nakagawa

    MECHANICS OF ADVANCED MATERIALS AND STRUCTURES 16 (7) 536-541 2009年

    出版者・発行元:TAYLOR & FRANCIS INC

    DOI: 10.1080/15376490903133400  

    ISSN:1537-6494

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    We study numerically and experimentally the nonlinear dynamic bending and sensing behavior of clamped-clamped functionally graded piezoelectric transducers under alternating current (AC) voltage. The contribution of domain wall motion to the elastic compliance, piezoelectric coefficient and dielectric permittivity in soft lead zirconate titanate (PZT) layers is evaluated, and a nonlinear finite element analysis is performed to discuss the effects of the amplitude and frequency of input voltage, number of layers and property gradation on the sound pressure, output voltage, and internal stresses and electric field for the transducers. In order to confirm the numerical results, bending tests on functionally graded piezoelectric transducers are conducted, and the sound pressure and output voltage are measured.

  236. Mixed-mode interlaminar fracture and damage characterization in woven fabric-reinforced glass/epoxy composite laminates at cryogenic temperatures using the finite element and improved test methods 査読有り

    Yasuhide Shindo, Susumu Takahashi, Torno Takeda, Furnio Narita, Shinya Watanabe

    ENGINEERING FRACTURE MECHANICS 75 (18) 5101-5112 2008年12月

    出版者・発行元:PERGAMON-ELSEVIER SCIENCE LTD

    DOI: 10.1016/j.engfracmech.2008.07.009  

    ISSN:0013-7944

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    The present research examines experimentally and analytically the mixed-mode interlaminar fracture and damage behavior of glass fiber reinforced polymer (GFRP) woven laminates at cryogenic temperatures. The mixed-mode bending (MMB) tests were performed with the improved test apparatus, at room temperature, liquid nitrogen temperature (77 K) and liquid helium temperature (4 K). The energy release rates at the onset of delamination crack propagation were evaluated for the woven GFRP specimens using both beam theory and finite element analysis. The fracture surfaces were also examined to verify the fracture mechanisms. In addition, the initiation and growth of damage in the specimens were predicted by a damage analysis, and the damage effect on the mixed-mode interlaminar fracture properties at cryogenic temperatures was explored. (c) 2008 Elsevier Ltd. All rights reserved.

  237. Interfacial Damage Effect on the Cryogenic Mechanical Response of Carbon Nanotube-Based Composites under Bending 査読有り

    Y. Shindo, Y. Mito, T. Takeda, Y. Kuronuma, F. Narita

    Advances in Theoretical and Applied Mechanics 1 (8) 361-377 2008年12月

  238. Scattering of elastic waves by a diamond shaped inclusion with cracks 査読有り

    Yasuhide Shindo, Tasuku Nakamura, Fumio Narita

    ACTA MECHANICA 200 (3-4) 239-246 2008年10月

    出版者・発行元:SPRINGER WIEN

    DOI: 10.1007/s00707-008-0011-0  

    ISSN:0001-5970

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    This paper studies the scattering of in-plane compressional and shear waves by a diamond shaped inclusion with cracks using the boundary element method. The special case that the shape of the diamond becomes square is also considered. Numerical calculations are carried out for the limited cases of diamond shaped hole and rigid inclusions, and the effects of frequency and inclusion shape on the scattering cross section and dynamic stress intensity factor are shown in graphical form. The results where the elastic properties of the inclusion are the same as those of the matrix are also discussed.

  239. Nonlinear Dynamic Response and Self-Sensing of Functionally Graded Piezoelectric Transducers 査読有り

    F. Narita, J. Nakagawa, Y. Shindo

    XXII International Congress of Theoretical and Applied Mechanics CD-ROM Proceedings, Edited by J. Denier, M. D. Finn and T. Mattner 10429 2008年8月

  240. Dynamic Fatigue Behavior of Cracked Piezoelectric Ceramics in Three-Point Bending under Electromechanical Loading 査読有り

    Y. Shindo, F. Narita, M. Hirama

    XXII International Congress of Theoretical and Applied Mechanics CD-ROM Proceedings, Edited by J. Denier, M. D. Finn and T. Mattner 11021 2008年8月

  241. Transverse Crack Behavior in Satin Woven Carbon Fiber Reinforced/Epoxy Composite Laminates at Cryogenic Temperatures 査読有り

    S. Watanabe, Y. Shindo, T. Takeda, F. Narita

    XXII International Congress of Theoretical and Applied Mechanics CD-ROM Proceedings, Edited by J. Denier, M. D. Finn and T. Mattner 11576 2008年8月

  242. The influence of magnetic field on the fracture toughness of soft ferromagnetic materials 査読有り

    Yasuhide Shindo, Itaru Shindo, Fumio Narita

    ENGINEERING FRACTURE MECHANICS 75 (10) 3010-3019 2008年7月

    出版者・発行元:PERGAMON-ELSEVIER SCIENCE LTD

    DOI: 10.1016/j.engfracmech.2007.12.015  

    ISSN:0013-7944

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    This paper studies the effect of magnetic fields on the fracture toughness in nickel iron soft ferromagnetic materials. Tensile tests were conducted on single-edge cracked plate specimens in the bore of a superconducting magnet at room temperature, and the critical load was determined. The magnetoelastic analysis of a soft ferromagnetic strip with a single-edge crack was also performed, and the magnetic stress intensity factor was calculated. Based on the magnetic stress intensity factor, the fracture toughness was then obtained. (c) 2008 Elsevier Ltd. All rights reserved.

  243. Cryogenic mechanical response of multilayer satin weave CFRP composites with cracks 査読有り

    S. Watanabe, Y. Shindo, T. Takeda, F. Narita

    MECHANICS OF COMPOSITE MATERIALS 44 (4) 331-340 2008年7月

    出版者・発行元:SPRINGER

    DOI: 10.1007/s11029-008-9025-x  

    ISSN:0191-5665

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    We deal with the thermomechanical response of multilayer satin weave carbon-fiber-reinforced polymer (CFRP) laminates with internal and/or edge cracks and temperature-dependent material properties subjected to tensile loading at cryogenic temperatures. The composite material is assumed to be under the generalized plane strain. Cracks are located in the transverse fiber bundles and extend to the interfaces between two fiber bundles. A finite-element model is employed to study the influence of residual thermal stresses on the mechanical behavior of multilayer CFRP woven laminates with cracks. Numerical calculations are carried out, and Young's modulus and stress distributions near the crack tip are shown graphically.

  244. Mode II interlaminar fracture and damage evaluation of GFRP woven laminates at cryogenic temperatures using the 4ENF specimen 査読有り

    Yasuhide Shindo, Takashi Sato, Fumio Narita, Kazuaki Sanada

    JOURNAL OF COMPOSITE MATERIALS 42 (11) 1089-1101 2008年6月

    出版者・発行元:SAGE PUBLICATIONS LTD

    DOI: 10.1177/0021998308090451  

    ISSN:0021-9983

    詳細を見る 詳細を閉じる

    This article focuses on understanding the Mode II interlaminar fracture and damage behavior of glass fiber reinforced polymer (GFRP) woven laminates at cryogenic temperatures. A four point bend, end notched flexure (4ENF) test is performed at room temperature (RT), liquid nitrogen temperature (77 K) and liquid helium temperature (4 K), and an R-curve characterization is conducted for determining the mode II cryogenic fracture properties of GFRP woven laminates. The test configuration is also analyzed by finite element analysis coupled with damage. The damage distributions within the 4ENF specimens are predicted, and the effect of damage on the Mode II energy release rate is examined. This work is the first application of failure criteria (Hoffman criterion and maximum strain criterion) to the description of the R-curve behavior and interlaminar fracture toughness values of woven laminate ENF specimens at cryogenic temperatures.

  245. Interlaminar Fracture and Damage in Woven GFRP Laminates at Cryogenic Temperatures 査読有り

    Y. Shindo, T. Takeda, F. Narita

    Advances in Heterogeneous Material Mechanics 2008 2008年6月

  246. Scattering of elastic waves by a star shaped inclusion 査読有り

    Yasuhide Shindo, Fumio Narita, Tasuku Nakamura

    ZAMM-ZEITSCHRIFT FUR ANGEWANDTE MATHEMATIK UND MECHANIK 88 (3) 191-198 2008年3月

    出版者・発行元:WILEY-V C H VERLAG GMBH

    DOI: 10.1002/zamm.200700088  

    ISSN:0044-2267

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    This paper is concerned with the scattering of in-plane compressional (P) and shear (SV) waves by boomerang, three-, four-, five-, and six-pointed star shaped inclusions using a boundary element method. Special case when the shape of the four-pointed star becomes square is also considered. Numerical examples are given for some star shapes of the inclusion, and the scattering cross sections are plotted as a function of frequency. The response simplifies for the limited cases of a hole and a rigid inclusion, but with quite different behavior for each. (C) 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  247. 1234 傾斜機能圧電カンチレバートランスデューサの動的電気力学応答と自己センシング(J10-4 マイクロ・ナノ材料システムの力学と強度・機能評価(4) 形状記憶・電磁力学特性評価,ジョイントセッション,21世紀地球環境革命の機械工学:人・マイクロナノ・エネルギー・環境)

    成田 史生, 進藤 裕英

    年次大会講演論文集 2008 313-314 2008年

    出版者・発行元:一般社団法人日本機械学会

    DOI: 10.1299/jsmemecjo.2008.6.0_313  

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    This paper studies the activity and sensitivity of functionally graded piezoelectric cantilever transducers under electromechanical loading through numerical and experimental characterizations. A phenomenological model of domain wall motion in alternating current (AC) electric fields is used, and a nonlinear three-dimensional finite element method is employed to simulate the dynamic response of functionally graded piezoelectric cantilever transducers. The effects of AC electric field amplitude and frequency, number of layers, and property gradation on the output voltage, deflection and internal stresses of the transducers are examined. Experimental results, which verify the model, are also presented using functionally graded piezoelectric bimorphs.

  248. Thermal-Mechanical Response of Cracked Satin Weave CFRP Composites at Cryogenic Temperatures 査読有り

    S. Watanabe, Y. Shindo, F. Narita, T. Takeda

    Advances in Cryogenic Engineering 54 227-234 2008年

    DOI: 10.1063/1.2900350  

  249. Effect of Magnetic Fields on the Bending Behavior of Giant Magnetostrictive Laminated Actuators 査読有り

    Y. Shindo, F. Narita, T. Nakamura

    Applied Mechanics in the Americas 12 13-16 2008年1月

  250. Thermal-Mechanical Response of Cracked Satin Weave CFRP Composites at Cryogenic Temperatures 査読有り

    S. Watanabe, Y. Shindo, F. Narita, T. Takeda

    Advances in Cryogenic Engineering 54 227-234 2008年1月

    DOI: 10.1063/1.2900350  

  251. Effects of electric field and poling on the response of multilayer piezoelectric film actuators with partial electrodes 査読有り

    Yasuhide Shindo, Furnio Narita, Mitsuru Hirama

    BEHAVIOR AND MECHANICS OF MULTIFUNCTIONAL AND COMPOSITE MATERIALS 2008 6929 692927-1-692927-8 2008年

    出版者・発行元:SPIE-INT SOC OPTICAL ENGINEERING

    DOI: 10.1117/12.775427  

    ISSN:0277-786X

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    The electromechanical field concentrations due to surface and internal electrodes in multilayer piezoelectric film actuators are investigated through numerical and experimental characterization. A nonlinear finite element analysis is carried out to discuss the effects of electric field and poling on the displacement and internal electromechanical fields in fully and partially poled piezoelectric actuators, by introducing models for polarization switching. Displacement measurements are also performed for the actuators, and a comparison of the predictions with experimental data is conducted.

  252. The application of the boundary element method to the problem of wave diffraction from a diamond shaped inclusion 招待有り 査読有り

    Yasuhide Shindo, Tasuku Nakamura, Fumio Narita

    Open Mechanics Journal 2 (1) 62-66 2008年

    DOI: 10.2174/1874158400802010062  

    ISSN:1874-1584

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    We investigate the scattering of in-plane compressional (P) and shear (SV) waves by diamond shaped inclusions using a boundary element method. Special case that the shape of the diamond becomes square is also considered. Numerical results for some diamond shapes of the inclusion are obtained, and the effects of frequency on the scattering cross sections are discussed in detail. The response simplifies for the limited cases of a hole and a rigid inclusion, but with quite different behavior for each. Calculations for a diamond shaped SiC-fiber-reinforced Al composite are also carried out, and the results are shown graphically. © Shindo et al.

  253. Nonlinear bending characteristics and sound pressure level of functionally graded piezoelectric actuators under AC electric fields: simulation and experiment 査読有り

    Yasuhide Shindo, Fumio Narita, Jun Nakagawa

    SMART MATERIALS & STRUCTURES 16 (6) 2296-2301 2007年12月

    出版者・発行元:IOP PUBLISHING LTD

    DOI: 10.1088/0964-1726/16/6/032  

    ISSN:0964-1726

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    This paper describes the results of our numerical and experimental studies of the nonlinear electromechanical response in functionally graded piezoelectric actuators under alternating current (AC) electric fields. A nonlinear finite-element method is employed to simulate the dynamic bending of clamped-clamped functionally graded piezoelectric bimorphs. A phenomenological model of domain wall motion is used in the computation, and the effects of AC electric field amplitude and frequency, number of layers and property gradation on the sound pressure level, deflection and internal stresses of the actuators are examined. The sound pressure level is also measured to validate the numerical predictions, and comparison is made between numerical results and experimental data.

  254. Delayed Fracture of the Piezoelectric Ceramics under Electric Fields in Three-Point Bending 査読有り

    F. Narita, Y. Shindo, M. Hirama

    Proceedings of IMECE2007 2007 41165-1-41165-10 2007年11月

    出版者・発行元:一般社団法人日本機械学会

    DOI: 10.1299/jsmemecjo.2007.1.0_205  

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    2007 ASME International Mechanical Engineering Congress and Exposition (November 11-15, 2007, Seattle, Washington, U.S.A.)

  255. Electroelastic intensification and domain switching near a plane strain crack in a rectangular piezoelectric material 招待有り 査読有り

    Yasuhide Shindo, Fumio Narita, Fumitoshi Saito

    JOURNAL OF MECHANICS OF MATERIALS AND STRUCTURES 2 (8) 1525-1540 2007年10月

    出版者・発行元:MATHEMATICAL SCIENCE PUBL

    DOI: 10.2140/jomms.2007.2.1525  

    ISSN:1559-3959

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    We study the effects of crack face boundary conditions and localized polarization switching on the piezoelectric fracture. This paper consists of two parts. In the first part, the electroelastic problem of an infinite piezoelectric material with a crack is formulated by means of integral transforms, and the exact solution is obtained. The electroelastic fields are expressed in closed form. The fracture mechanics parameters, such as energy release rate, are obtained for the permeable, impermeable and open crack models. In the second part, finite element analysis is carried out to study the crack behavior in a rectangular piezoelectric material by introducing a model for polarization switching in local areas of electroelastic field concentrations. A nonlinear behavior induced by localized polarization switching is observed between the fracture mechanics parameters and applied electric field.

  256. Electroelastic response of a flat annular crack in a piezoelectric fiber surrounded by an elastic medium 査読有り

    Y. Shindo, S. Lin, F. Narita

    JOURNAL OF ENGINEERING MATHEMATICS 59 (1) 83-97 2007年9月

    出版者・発行元:SPRINGER

    DOI: 10.1007/s10665-006-9072-z  

    ISSN:0022-0833

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    Following the theory of linear piezoelectricity, the electroelastic problem of a flat annular crack in a piezoelectric fiber embedded in an elastic medium is considered. Fourier and Hankel transform techniques are employed to formulate the mixed-boundary-value problem as a singular integral equation. The stress-intensity factor, energy-release rate and energy-density factor are computed for some piezoelectric composites, and the influence of applied electric fields on the normalized values is displayed graphically.

  257. Cyclic fatigue crack growth in three-point bending PZT ceramics under electromechanical loading 査読有り

    Fumio Narita, Yasuhide Shindo, Fumitoshi Saito

    JOURNAL OF THE AMERICAN CERAMIC SOCIETY 90 (8) 2517-2524 2007年8月

    出版者・発行元:BLACKWELL PUBLISHING

    DOI: 10.1111/j.1551-2916.2007.01774.x  

    ISSN:0002-7820

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    This paper investigates experimentally and analytically the cyclic fatigue crack growth in piezoelectric ceramics under electromechanical loading. Cyclic crack growth tests were conducted on lead zirconate titanate (PZT) ceramics subjected to de electric fields, and a finite element analysis was used to calculate the maximum energy release rate for the permeable crack model. Based on bending experiments using single-edge precracked-beam specimens, cyclic fatigue crack growth rates are found to be sensitive to the maximum energy release rate and applied dc electric fields. Possible mechanisms for crack growth were discussed by scanning electron microscope examination of the fracture surface of the PZT ceramics.

  258. Characteristics of Detection and Response in Functionally Graded Piezoelectric Sensors and Actuators 招待有り 査読有り

    Y. Shindo, F. Narita, J. Nakagawa, Y. Mito

    International Journal of Advances in Mechanics and Applications of Industrial Materials 1 (1) 79-86 2007年8月

  259. Electroelastic field concentrations and polarization switching induced by circular electrode at the interface of piezoelectric disk composites 査読有り

    Fumio Narita, Yasuhide Shindo, Masaru Mikami

    EUROPEAN JOURNAL OF MECHANICS A-SOLIDS 26 (3) 394-404 2007年5月

    出版者・発行元:GAUTHIER-VILLARS/EDITIONS ELSEVIER

    DOI: 10.1016/j.euromechsol.2006.07.001  

    ISSN:0997-7538

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    The electromechanical field concentrations due to circular electrode at the interface of piezoelectric disk composites have been discussed. This paper consists of two parts. In the first part, the problem of an internal electrode embedded at the interface of two dissimilar semi-infinite piezoelectric solids was formulated by means of Hankel transforms, and the solution was solved exactly. In the second part, finite element analysis was carried out to study electromechanical response in piezoelectric disk composites containing a circular electrode at the interface by introducing a model for polarization switching in local areas of field concentrations. A nonlinear behavior induced by localized polarization switching was observed between the strain and the voltage applied to the electrode. (c) 2006 Elsevier Masson SAS. All rights reserved.

  260. Mixed-Mode Interlaminar Fracture and Damage of Woven GFRP Laminates at Cryogenic Temperatures 査読有り

    Y. Shindo, F. Narita, S. Takahashi, T. Sato

    Conference Papers, AIAA2007 2408-1-2408-10 2007年4月

  261. Axially poled solid cylinder under tension with a flat annular crack 査読有り

    Fumio Narita, Yasuhide Shindo, Sen Lin

    ZAMM-ZEITSCHRIFT FUR ANGEWANDTE MATHEMATIK UND MECHANIK 87 (4) 278-289 2007年4月

    出版者・発行元:WILEY-V C H VERLAG GMBH

    DOI: 10.1002/zamm.200610301  

    ISSN:0044-2267

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    We investigate the electroelastic response of a flat annular crack in a solid piezoelectric cylinder of finite radius under mode I loading. By the use of Fourier and Hankel transforms, the mixed boundary value problem is reduced to a singular integral equation. Numerical values on the stress intensity factor, energy release rate, and energy density factor for piezoelectric cylinders are obtained to show the influence of applied electric fields, and the results are presented in graphical form. Special cases of a penny-shaped crack and a circumferential edge crack are also discussed. (C) 2006 WILEY-VCH Verlag GmbH & Co. KGaA. Weinheim

  262. Effect of magnetic field on fatigue crack propagation of single-edge cracked soft ferromagnetic specimens under mode I loading 査読有り

    Yasuhide Shindo, Itaru Shindo, Fumio Narita

    JOURNAL OF TESTING AND EVALUATION 35 (2) 151-156 2007年3月

    出版者・発行元:AMER SOC TESTING MATERIALS

    ISSN:0090-3973

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    The purpose of this paper is to investigate the effect of magnetic field on the fatigue crack growth behavior of nickel iron soft ferromagnetic materials under Mode I loading. Fatigue crack growth tests were conducted using single-edge cracked tension specimens in a magnetic field, and the effects of magnetic field and loading condition on the crack growth rates were examined. Magnetic field effect on the stress intensity factor range also was discussed for a single-edge cracked soft ferromagnetic strip. The fracture surfaces were examined by scanning electron microscopy to correlate with fatigue characteristics.

  263. Bending Behavior of Functionally Graded Piezoelectric Laminated Actuators under Electric Fields 査読有り

    Y. Shindo, F. Narita

    Key Engineering Materials 336/338 2619-2623 2007年1月

  264. Testing and analysis of high frequency electroelastic characteristics of piezoelectric transformers 査読有り

    F. Narita, Y. Shindo, F. Saito, M. Mikami

    ARCHIVES OF MECHANICS 59 (2) 119-131 2007年

    出版者・発行元:POLISH ACAD SCIENCES INST FUNDAMENTAL TECHNOL RES

    ISSN:0373-2029

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    THIS ARTICLE PRESENTS the results of experimental and numerical work on the dynamic electroelastic response of Rosen-type piezoelectric transformers. Experiments were conducted to measure the electrical impedance, phase angle and voltage gain at various frequencies. The three-dimensional finite element method was also employed to solve the coupled electro-elastic boundary value problem. The electrical impedance, phase angle and voltage gain were calculated and a comparison was made between experiment and simulation. The effects of load resistance and capacitance on the voltage gain and electroelastic field concentrations were also discussed in detail.

  265. Fatigue of cracked PZT ceramics in three-point bending under electric fields 査読有り

    Fumio Narita, Yasuhide Shindo, Fumitoshi Saito

    BEHAVIOR AND MECHANICS OF MULTIFUNCTIONAL AND COMPOSITE MATERIALS 2007 6526 65262O-1-65262O-8 2007年

    出版者・発行元:SPIE-INT SOC OPTICAL ENGINEERING

    DOI: 10.1117/12.713966  

    ISSN:0277-786X

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    This paper presents the results of an analytical and experimental investigation in fatigue crack growth behavior of piezoelectric ceramics under electromechanical loading. Static fatigue tests are performed in three-point bending with the single-edge precracked-beam piezoelectric specimens under electric fields. Time-to-failure under different mechanical loads and electric fields are measured, and the effect of applied electric fields on the energy release rate vs lifetime curves are discussed, with combination with the finite element method. Cyclic crack growth tests are also conducted on the same piezoelectric specimens under electric fields, and the fatigue crack growth rate vs maximum energy release rate curves are examined.

  266. Static fatigue behavior of cracked piezoelectric ceramics in three-point bending under electric fields 査読有り

    Yasuhide Shindo, Fumio Narita, Fumitoshi Saito

    JOURNAL OF THE EUROPEAN CERAMIC SOCIETY 27 (10) 3135-3140 2007年

    出版者・発行元:ELSEVIER SCI LTD

    DOI: 10.1016/j.jeurceramsoc.2006.11.078  

    ISSN:0955-2219

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    This paper describes an experimental and analytical study on the static fatigue behavior of piezoelectric ceramics under electromechanical loading. Static fatigue tests were carried out in three-point bending with the single-edge precracked-beam specimens. The crack was created perpendicular to the poling direction. Time-to-failure under different mechanical loads and dc electric fields were obtained from the experiment. Microscopic,examination of the fracture surface of the piezoelectric ceramics was performed as well. A finite element analysis was also made, and the applied energy release rate for the permeable crack model was calculated. The effect of applied dc electric fields on the energy release rate versus lifetime curve is examined. The most important conclusion we reach is that the lifetimes for the piezoelectric specimens under a positive electric field are much shorter than the failure times of specimens under a negative electric field for the same mechanical load level. (C) 2006 Elsevier Ltd. All rights reserved.

  267. An experimental-computational approach to the investigation of tensile properties and damage evolution in woven GFRP laminates at cryogenic temperatures 査読有り

    Yasuhide Shindo, Satoru Takano, Fumio Narita, Katsumi Horiguchi

    MECHANICS OF ADVANCED MATERIALS AND STRUCTURES 14 (5) 329-346 2007年

    出版者・発行元:TAYLOR & FRANCIS INC

    DOI: 10.1080/15376490600910704  

    ISSN:1537-6494

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    This paper presents an experimental and analytical investigation of the effect of specimen geometry on the tensile properties and damage behavior of glass fiber reinforced polymer woven laminates at cryogenic temperatures. Cryogenic tensile tests were performed on three types of specimens, and acoustic emission monitoring was employed to characterize the damage development during loading. A two-dimensional finite element analysis was also carried out for three tensile test specimens in order to have a thorough understanding of the progressive failure behavior. A comparison was made between simulation and experiment.

  268. Nonlinear dynamic deflection and sound level in functionally graded piezoelectric actuators under AC electric fields 査読有り

    Yasuhide Shindo, Furnio Narita, Jun Nakagawa

    PROCEEDINGS OF THE 5TH INTERNATIONAL CONFERENCE ON NONLINEAR MECHANICS 1628-1632 2007年

    出版者・発行元:SHANGHAI UNIV PRESS

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    We examine the nonlinear bending behavior of functionally graded piezoelectric actuators under AC electric fields in a combined numerical and experimental investigation. The functionally graded piezoelectric actuators consist of many thin soft PZT layers. The contribution of domain wall motion to the elastic compliance, piezoelectric coefficient and dielectric permittivity in PZT layers is evaluated, and a nonlinear finite element analysis is done to examine the effects of the amplitude and frequency of electric fields, number of layers, and property gradation on the deflection, sound level and internal stresses for actuators. In order to confirm the numerical results, bending tests on various functionally graded piezoelectric actuators are performed, and the deflection and sound level are measured.

  269. Mode I crack growth rate of a ferromagnetic elastic strip in a uniform magnetic field 査読有り

    Yasuhide Shindo, Fumio Narita, Katsumi Horiguchi, Tetsu Komatsu

    ACTA MATERIALIA 54 (19) 5115-5122 2006年11月

    出版者・発行元:PERGAMON-ELSEVIER SCIENCE LTD

    DOI: 10.1016/j.actamat.2006.06.048  

    ISSN:1359-6454

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    The theory of ferromagnetii, elastic materials of multidomain structure is applied to develop a crack growth rate equation of a finite crack in a soft ferromagnetic material under mode I tensile loading and uniform magnetic field. The plane strain and plane stress problems are considered Dugdale's assumption regarding the plastic zone in metals is applied to estimate the effect of yield around the crack tip. The accimulated plastic displacement criterion is used for developing a solution for the crack growth rate. Numerical values of crack growth rate are obtained for a soft ferromagnetic strip with a single-edge crack and the results are displayed graphically. Crack growth rate tests are also conducted on nickel-iron soft magnetic materials with a single-edge cracked plate specimen geometry in the bore of a superconducting magnet, and a comparison is made between numerical results and experimental data. (c) 2006 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  270. Tensile and damage behavior of plain weave glass/epoxy composites at cryogenic temperatures 査読有り

    Y. Shindo, S. Takano, F. Narita, K. Horiguchi

    FUSION ENGINEERING AND DESIGN 81 (20-22) 2479-2483 2006年11月

    出版者・発行元:ELSEVIER SCIENCE SA

    DOI: 10.1016/j.fusengdes.2006.07.059  

    ISSN:0920-3796

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    This paper relates to experimental and analytical work on the cryogenic tensile and damage behavior of glass fiber reinforced polymer woven laminates. Tensile tests were performed on specimens with gradual transition region at room temperature, 77, 20, and 4 K. During the tensile tests, acoustic emission monitoring was employed to characterize the damage development. A two-dimensional finite element model was also used to perform the progressive failure analysis. (c) 2006 Elsevier B.V. All rights reserved.

  271. Analysis of mode II interlaminar fracture and damage behavior in end notched flexure testing of GFRP woven laminates at cryogenic temperatures 査読有り

    Y. Shindo, F. Narita, T. Sato

    ACTA MECHANICA 187 (1-4) 231-240 2006年11月

    出版者・発行元:SPRINGER WIEN

    DOI: 10.1007/s00707-006-0357-0  

    ISSN:0001-5970

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    Interlaminar fracture and damage behavior of glass fiber reinforced polymer (GFRP) woven laminates at cryogenic temperatures is investigated for end notched flexure (ENF) pure Mode II configuration. The corrected beam theory (CBT) and finite element analysis (FEA) are used to calculate the Mode II interlaminar fracture toughness of ENF specimen at room temperature (RT), liquid nitrogen temperature (77 K) and liquid helium temperature (4 K). A FEA coupled with damage is also employed to study the damage distributions within the specimen and to examine the effect of damage on the Mode II energy release rate. The numerical results show that damage occurs at the matrix and causes a decrease in the energy release rate. The technique presented can be efficiently used for the characterization of cryogenic Mode II interlaminar fracture and damage behavior of woven laminate ENF specimens.

  272. Mode I fatigue delamination growth in GFRP woven laminates at low temperatures 査読有り

    Yasuhide Shindo, Akihiro Inamoto, Fumio Narita, Katsumi Horiguchi

    ENGINEERING FRACTURE MECHANICS 73 (14) 2080-2090 2006年9月

    出版者・発行元:PERGAMON-ELSEVIER SCIENCE LTD

    DOI: 10.1016/j.engfracmech.2006.03.015  

    ISSN:0013-7944

    詳細を見る 詳細を閉じる

    The cryogenic fatigue delamination behavior of glass fiber reinforced polymer woven laminates under Mode I loading has been investigated experimentally and numerically. Fatigue delamination tests were conducted using double cantilever beam specimens at room temperature, liquid nitrogen temperature (77 K) and liquid helium temperature (4 K). Fracture surface examination using scanning electron microscopy revealed delamination mechanisms under fatigue loading. A finite element analysis was also employed to calculate the J-integral range and damage distributions. The effects of temperature and loading condition on the fatigue delamination growth rates were discussed. (c) 2006 Elsevier Ltd. All rights reserved.

  273. Mode III interlaminar fracture behavior of glass fiber reinforced polymer woven laminates at 293 to 4 k 査読有り

    Victor Rizov, Yasuhide Shindo, Katsumi Horiguchi, Fumio Narita

    APPLIED COMPOSITE MATERIALS 13 (5) 287-304 2006年9月

    出版者・発行元:SPRINGER

    DOI: 10.1007/s10443-006-9008-9  

    ISSN:0929-189X

    詳細を見る 詳細を閉じる

    This paper deals with mode III delamination properties of glass fiber reinforced polymer woven laminates at room temperature (293 K), liquid nitrogen temperature (77 K), gas helium temperature (20 K), and liquid helium temperature (4 K). In order to evaluate these properties, the Split Cantilever Beam (SCB) fracture test is performed. The load is applied to a test specimen through a set of identical grips in order to reduce (in some degree) the mode II loading at the free edges. A three-dimensional finite element analysis is used to study the stress and strain state of the specimens and to interpret the experimental measurements. The strain energy release rate is calculated by using the virtual crack closure technique. It is found that the strain energy release rate is dominated by the mode III component. A non-uniform distribution of the strain energy release rate along the delamination front is obtained with mode III component having maximum at the center of the delamination front, while mode II component increases towards the free edges. The strain energy release rate is also determined using the crack closure technique. A finite element analysis is also carried out to calculate the stress intensity factors for the SCB specimens. The fracture surfaces are examined by scanning electron microscopy to identify the fracture mechanisms. The most important conclusion from the present study is that at temperature lowering from 293 to 20 K the mode III fracture toughness increases, further cooling to 4 K produces a toughness decrease.

  274. Three-dimensional electroelastic analysis of functionally graded piezoelectric plate via state vector approach 査読有り

    Shisheng Fang, Yasuhide Shindo, Fumio Narita, Sen Lin

    ZAMM-ZEITSCHRIFT FUR ANGEWANDTE MATHEMATIK UND MECHANIK 86 (8) 628-641 2006年8月

    出版者・発行元:WILEY-V C H VERLAG GMBH

    DOI: 10.1002/zamm.200510270  

    ISSN:0044-2267

    詳細を見る 詳細を閉じる

    Three-dimensional electroelastic formulation is developed to study the response of functionally graded rectangular piezoelectric structures/plates. The electroelastric properties are assumed to vary linearly and nonlinearly in the thickness direction, and exact expressions for all relevant electroelastic variables are obtained through a state vector methodology. Numerical examples are presented and discussed for simply-supported bi-layer actuators with functionally graded piezoelectric layers under surface and/or internal electric potential loads. The results presented in this paper are important in the design and characterization of functionally graded piezoelectric materials in applications as microelectromechanical systems. (C) 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  275. Magnetoelastic analysis and tensile testing of a soft ferromagnetic strip with a single-edge crack 査読有り

    Yasuhide Shindo, Tetsu Komatsu, Fumio Narita, Katsumi Horiguchi

    JOURNAL OF APPLIED PHYSICS 100 (3) 034513 2006年8月

    出版者・発行元:AMER INST PHYSICS

    DOI: 10.1063/1.2222068  

    ISSN:0021-8979

    詳細を見る 詳細を閉じる

    This article describes the results of an analytical and experimental study of the effect of magnetic fields on the stress intensity factors in a soft ferromagnetic strip under uniaxial tension. The linear magneto-elastic problem for a soft ferromagnetic strip with a single-edge crack is analyzed. Fourier transform techniques are used to formulate the mixed boundary value problem as a singular integral equation. The stress intensity factors are obtained for several values of material and geometrical parameters, and magnetic field. Static experiments are also conducted on nickel-iron soft magnetic materials with a single-edge cracked plate specimen geometry in the bore of a superconducting magnet at room temperature. A strain gauge method is employed in experiments to determine the stress intensity factor. A comparison of the stress intensity factor is made between theory and experiment, and the agreement is good for the magnetic field considered. (c) 2006 American Institute of Physics.

  276. Nonlinear dynamic bending and domain wall motion in functionally graded piezoelectric actuators under AC electric fields: Simulation and experiment 査読有り

    Y Shindo, F Narita, M Mikami, F Saito

    JSME INTERNATIONAL JOURNAL SERIES A-SOLID MECHANICS AND MATERIAL ENGINEERING 49 (2) 188-194 2006年4月

    出版者・発行元:JAPAN SOC MECHANICAL ENGINEERS

    DOI: 10.1299/jsmea.49.188  

    ISSN:1344-7912

    詳細を見る 詳細を閉じる

    This paper describes the results of our numerical and experimental studies of the nonlinear bending behavior due to domain wall motion in functionally graded piezoelectric actuator under alternating current electric fields. A nonlinear three-dimensional finite element method is employed to simulate the dynamic response of cantilever functionally graded piezoelectric actuator. A phenomenological model of domain wall motion is used in computation, and the effects of ac electric field amplitude and frequency, number of layers, and property gradation on the deflection and internal stresses of the functionally graded bimorphs are examined. It is shown that the predicted deflection results, obtained from the numerical model, agree well with the corresponding experimental results.

  277. Magnetic stress intensity factor for an edge crack in a soft ferromagnetic elastic half-plane under tension 査読有り

    Y Shindo, T Komatsu, F Narita, K Horiguchi

    ACTA MECHANICA 182 (3-4) 183-193 2006年4月

    出版者・発行元:SPRINGER WIEN

    DOI: 10.1007/s00707-005-295-2  

    ISSN:0001-5970

    詳細を見る 詳細を閉じる

    This paper applies the theory for magnetoelasticity to solve the plane problem of an edge crack in a soft ferromagnetic half-plane subjected to a far-field tension and a uniform magnetic field. Fourier transform techniques are used to formulate the mixed boundary value problem as a singular integral equation. The stress intensity factor is calculated and is shown graphically. Tensile tests are also performed on a cracked ferromagnetic plate with strain gage technique, and the numerical results are compared with the test data.

  278. 318 織物GFRP積層材料の極低温モードII層間破壊・損傷挙動(GS1(4) 変形,破壊挙動,疲労,クリープ,衝撃)

    佐藤 昂, 進藤 裕英, 成田 史生, 真田 和昭

    材料力学部門講演会講演論文集 2006 153-154 2006年

    出版者・発行元:一般社団法人日本機械学会

    DOI: 10.1299/jsmezairiki.2006.0_153  

  279. 3446 磁場内における軟磁性帯板のモードIき裂進展速度(S15-3 機能材料,S15 先端材料システムの強度・機能評価とメゾメカニックス)

    進藤 裕英, 成田 史生, 堀口 勝三

    年次大会講演論文集 2006 603-604 2006年

    出版者・発行元:一般社団法人日本機械学会

    DOI: 10.1299/jsmemecjo.2006.1.0_603  

    詳細を見る 詳細を閉じる

    The theory of ferromagnetic elastic materials of multidomain structure is applied to develop a crack growth rate equation of a finite crack in a soft ferromagnetic material under Mode I tensile loading and uniform magnetic field. The plane strain and plane stress problems are considered. Dugdale's assumption regarding the plastic zone in metals is applied to estimate the effect of yield around the crack tip. The accumulated plastic displacement criterion is used for developing a solution for the crack growth rate. Numerical values of crack growth rate are obtained for a soft ferromagnetic strip with a single-edge crack and the results are displayed graphically. Crack growth rate tests are also conducted on nickel-iron soft magnetic materials with a single-edge cracked plate specimen geometry in the bore of a superconducting magnet, and a comparison is made between numerical results and experimental data.

  280. Tensile Behavior and Damage/Acoustic Emission Characteristics of Woven Glass Fiber Reinforced/Epoxy Composite Laminates at Cryogenic Temperatures 査読有り

    Y. Shindo, F. Narita, K. Horiguchi, S. Takano, T. Takeda, K. Sanada

    Advances in Cryogenic Engineering 52 249-256 2006年

    DOI: 10.1063/1.2192358  

  281. Tensile Behavior and Damage/Acoustic Emission Characteristics of Woven Glass Fiber Reinforced/Epoxy Composite Laminates at Cryogenic Temperatures 査読有り

    Y. Shindo, F. Narita, K. Horiguchi, S. Takano, T. Takeda, K. Sanada

    Advances in Cryogenic Engineering 52 249-256 2006年

    DOI: 10.1063/1.2192358  

  282. 23. Electroelastic Intensification and Polarization Switching near Crack in Rectangular Piezoelectric Body 査読有り

    Y. Shindo, F. Narita, M. Mikami, S. Lin

    Applied Mechanics in the Americas (Edited by Jeffrey W. Eischen, Guillermo Monsiváis Galindo) 11 91 2006年1月

  283. Electroelastic field concentrations and frequency properties of Rosen-type piezoelectric transformers 査読有り

    Fumio Narita, Yasuhide Shindo, Masaru Mikami

    SMART STRUCTURES AND MATERIALS 2006: ACTIVE MATERIALS: BEHAVIOR AND MECHANICS 6170 617026 2006年

    出版者・発行元:SPIE-INT SOC OPTICAL ENGINEERING

    DOI: 10.1117/12.657309  

    ISSN:0277-786X

    詳細を見る 詳細を閉じる

    This paper examines the dynamic electroelastic response of Rosen-type piezoelectric transformers in a combined experimental and numerical investigation. Experiments were performed to measure the electrical impedance and voltage gain at various frequencies. The finite element method was also used to solve the coupled electro-elastic boundary value problem. The electrical impedance and voltage gain were calculated and a comparison was made between experiment and simulation. The effects of load resistance and capacitance on the voltage gain and electroelastic field concentrations were also discussed.

  284. Analytical and experimental study of nonlinear bending response and domain wall motion in piezoelectric laminated actuators under ac electric fields 査読有り

    F Narita, Y Shindo, M Mikami

    ACTA MATERIALIA 53 (17) 4523-4529 2005年10月

    出版者・発行元:PERGAMON-ELSEVIER SCIENCE LTD

    DOI: 10.1016/j.actamat.2005.05.044  

    ISSN:1359-6454

    詳細を見る 詳細を閉じる

    We investigate the nonlinear bending behavior of piezoelectric laminated actuators as a function of the amplitude and frequency of large electric fields both analytically and experimentally. Laminated beam theory is expanded to allow for the cantilever piezoelectric/metal/piezoelectric actuator, and the effects of alternating current (ac) electric fields on the tip deflection are analyzed. A simple phenomenological model of a vibrating domain wall in electric fields is used, and the macroscopic actuator response is predicted. A nonlinear three-dimensional finite element analysis is also employed. Experimental results are presented to validate the predictions using bimorph-type bending actuators made with thin soft lead zirconate titanate (PZT) layers and a thin metal sheet. Calculations show reasonable agreement with the experimental data, and support a role for domain wall motion in the nonlinear material response of the soft PZT under ac electric fields. (c) 2005 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  285. Deformation and progressive failure behavior of woven-fabric-reinforced glass/epoxy composite laminates under tensile loading at cryogenic temperatures 査読有り

    T Takeda, S Takano, Y Shindo, F Narita

    COMPOSITES SCIENCE AND TECHNOLOGY 65 (11-12) 1691-1702 2005年9月

    出版者・発行元:ELSEVIER SCI LTD

    DOI: 10.1016/j.compscitech.2005.02.009  

    ISSN:0266-3538

    詳細を見る 詳細を閉じる

    This paper focuses on understanding the deformation and progressive failure behavior of glass/epoxy plain weave fabric-reinforced laminates subjected to Uniaxial tension at cryogenic temperatures. Cryogenic tensile tests were conducted on the woven-fabric laminates, and the damage development during loading was characterized by AE (acoustic emission) measuremerits. A finite clement model for progressive failure analysis of woven-fabric composite panels was also developed, and applied to simulate the "knee" behavior in the stress-strain responses and the damage behavior in the tensile test specimens. Failure of the epoxy resin matrix in the transverse fiber bundle was predicted to occur using the maximum strain failure criterion. The effect of strain concentrations due to the fabric architecture on the failure strain of the material was considered by incorporating the SVF (strain variation factor) from the meso-scale analysis of a woven-fabric composite unit into the macro-scale analysis of the specimens. A comparison was made between the finite element predictions and the experimental data, and the agreement is good. (c) 2005 Elsevier Ltd. All rights reserved.

  286. Electroelastic fracture mechanics of piezoelectric layered composites 招待有り 査読有り

    Y Shindo, F Narita, M Mikami

    JOURNAL OF INTELLIGENT MATERIAL SYSTEMS AND STRUCTURES 16 (7-8) 573-582 2005年7月

    出版者・発行元:SAGE PUBLICATIONS LTD

    DOI: 10.1177/1045389X05048329  

    ISSN:1045-389X

    詳細を見る 詳細を閉じる

    This paper develops a theoretical electroelastic fracture mechanics for piezoelectric layered composites. A piezoelectric layer bonded between two elastic or piezoelectric materials containing a crack normal to the interfaces is considered. The ends of the crack are situated at equal distances away from the interfaces. Both analytical and simulation methods are formulated to determine the effects of applied electric field and polarization switching on the fracture mechanics parameters such as stress intensity factor, energy release rate, and energy density factor. The results for the exact (permeable) and approximate (impermeable) boundary conditions are presented in graphical form.

  287. Bending and polarization switching of piezoelectric laminated actuators under electromechanical loading 査読有り

    F Narita, Y Shindo, K Hayashi

    COMPUTERS & STRUCTURES 83 (15-16) 1164-1170 2005年6月

    出版者・発行元:PERGAMON-ELSEVIER SCIENCE LTD

    DOI: 10.1016/j.compstruc.2004.08.025  

    ISSN:0045-7949

    詳細を見る 詳細を閉じる

    The static electromechanical displacement and polarization switching properties of piezoelectric laminated actuators under three point bending have been investigated theoretically, numerically and experimentally. A laminated beam theory is expanded to allow for piezoelectric/metal/piezoelectric actuator, and the effects of electromechanical loading on the displacements of the actuators are analyzed. A nonlinear three-dimensional finite element procedure which allows to compute the polarization switching behavior is also proposed. Three point bending tests are used to validate the numerical predictions, using laminated actuators made with thin soft lead zirconate titanate (PZT) piezoelectric layers and a thin metal sheet, and comparison is made between numerical results and experimental data. (c) 2005 Elsevier Ltd. All rights reserved.

  288. Acoustic emission and fracture behavior of GFRP woven laminates at cryogenic temperatures 査読有り

    Y Shindo, M Sumikawa, F Narita, K Sanada

    CRYOGENICS 45 (6) 439-449 2005年6月

    出版者・発行元:ELSEVIER SCI LTD

    DOI: 10.1016/j.cryogenics.2005.03.002  

    ISSN:0011-2275

    詳細を見る 詳細を閉じる

    This paper describes an experimental and analytical Study on fracture and damage behavior of GFRP woven laminates at cryogenic temperatures. CT (compact tension) tests were carried out at room temperature, liquid nitrogen temperature (77 K) and liquid helium temperature (4 K) to evaluate the critical values of the fracture mechanics parameters. During the CT tests, AE (acoustic emission) method was implemented. AE signals can identify the critical load at which gross failure occurs. A FEA (finite element analysis) was also applied to calculate the fracture mechanics parameters. The failure criteria (Hoffman criterion and maximum strain criterion) or the damage variable based on the continuum damage mechanics was incorporated into the model to interpret the experimental measurements and to study the damage distributions within the specimen. Several methods of calculating J-integral are discussed. (c) 2005 Elsevier Ltd. All rights reserved.

  289. Double torsion testing and finite element analysis for determining the electric fracture properties of piezoelectric ceramics 査読有り

    Y Shindo, F Narita, M Mikami

    JOURNAL OF APPLIED PHYSICS 97 (11) 114109 2005年6月

    出版者・発行元:AMER INST PHYSICS

    DOI: 10.1063/1.1925331  

    ISSN:0021-8979

    詳細を見る 詳細を閉じる

    This paper presents the results of an experimental and numerical investigation in electric fracture behavior of composite [Pb(Zr,Ti)O-3] double torsion (DT) specimens. DT tests were conducted on a commercial piezoelectric ceramic bonded between two metals. Fracture loads under different electric fields were obtained from the experiment. Nonlinear three-dimensional finite element analysis was also employed to calculate the energy release rate for DT specimens based on the exact (permeable) and approximate (impermeable) crack models. The effects of applied electric field and domain switching on the energy release rate are discussed, and the model predictions are compared with the results of the experiments. (C) 2005 American Institute of Physics.

  290. Dynamic Bending and Domain Wall Motion in Piezoelectric Laminated Actuators under AC Electric Fields 査読有り

    Y. Shindo, F. Narita, M. Mikami, K. Hayashi

    Third MIT Conference on Computational Fluid and Solid Mechanics, Computational Fluid and Solid Mechanics 2005 3 488-491 2005年6月

  291. Electroelastic fracture mechanics analysis of central active piezoelectric transformer 査読有り

    F Narita, S Lin, Y Shindo

    EUROPEAN JOURNAL OF MECHANICS A-SOLIDS 24 (3) 377-392 2005年5月

    出版者・発行元:GAUTHIER-VILLARS/EDITIONS ELSEVIER

    DOI: 10.1016/j.euromechsol.2005.01.001  

    ISSN:0997-7538

    詳細を見る 詳細を閉じる

    The theory of linear piezoelectricity is applied to solve the plane strain electroelastic problem of a central active piezoelectric transformer in presence of a crack located normal to the interfaces. The ends of the crack are situated at equal distances away from the interfaces. The problem of an infinite central active piezoelectric transformer is formulated by means of integral transforms and reduced to the solution of a system of Fredholm integral equations of the second kind. Numerical calculations are carried out, and the fracture mechanics parameters such as stress intensity factor, energy release rate and energy density factor based on both permeable and impermeable crack models are shown graphically and compared. (c) 2005 Elsevier SAS. All rights reserved.

  292. Characterization of Mode I fatigue crack growth in GFRP woven laminates at low temperatures 査読有り

    Y Shindo, A Inamoto, F Narita

    ACTA MATERIALIA 53 (5) 1389-1396 2005年3月

    出版者・発行元:PERGAMON-ELSEVIER SCIENCE LTD

    DOI: 10.1016/j.actamat.2004.11.032  

    ISSN:1359-6454

    詳細を見る 詳細を閉じる

    This paper describes an experimental and analytical study on the cryogenic fatigue behavior of glass fiber reinforced polymer woven laminates under Mode I loading. Fatigue crack growth rate tests were performed using compact tension specimens at room temperature, liquid nitrogen temperature (77 K), and liquid helium temperature (4 K). The fracture surfaces were also examined by scanning electron microscopy to correlate with the fatigue properties. A finite element method coupled with fatigue damage was adopted for the extensional analysis. The effects of temperature and loading condition on the fatigue crack growth rates are examined. (C) 2004 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  293. Electric Fracture and Polarization Switching of Piezoelectric Ceramics: Experiment and Finite Element Simulation 査読有り

    M. Karaiwa, F. Narita, Y. Shindo

    11th International Conference on Fracture, CD-ROM Proceedings 1179 2005年3月

  294. P54 片側縁き裂を有する強磁性帯板の磁気弾性解析・引張試験(変形-強度評価,ポスター講演3)

    小松 徹, 進藤 裕英, 成田 史生, 堀口 勝三

    材料力学部門講演会講演論文集 2005 531-532 2005年

    出版者・発行元:一般社団法人日本機械学会

    DOI: 10.1299/jsmezairiki.2005.0_531  

  295. 1733 Nonlinear Bending Behavior of Functionally Graded Piezoelectric Actuators under Electric Fields

    成田 史生, 進藤 裕英, 三上 賢, 斉藤 文利

    年次大会講演論文集 2005 369-370 2005年

    出版者・発行元:一般社団法人日本機械学会

    DOI: 10.1299/jsmemecjo.2005.1.0_369  

    詳細を見る 詳細を閉じる

    We present numerical and experimental results on the nonlinear bending behavior due to domain wall motion in functionally graded piezoelectric actuator under alternating current (ac) electric fields. A nonlinear finite element method is employed to analyze the dynamic response of functionally graded piezoelectric actuator. A phenomenological model of domain wall motion is used in computation, and the effects of ac electric field amplitude and frequency, number of layers, and property gradation on the deflection and internal stresses of the cantilever actuators are examined. Experimental results, which verify the model, are presented using a functionally graded bimorph. The numerical results agree very well with the experimental values.

  296. Magnetic stress intensity factors for two symmetric edge cracks in a soft ferromagnetic elastic strip under tension 査読有り

    Y Shindo, D Sekiya, F Narita, K Horiguchi

    JSME INTERNATIONAL JOURNAL SERIES A-SOLID MECHANICS AND MATERIAL ENGINEERING 48 (1) 7-13 2005年1月

    出版者・発行元:JAPAN SOC MECHANICAL ENGINEERS

    DOI: 10.1299/jsmea.48.7  

    ISSN:1344-7912

    詳細を見る 詳細を閉じる

    The magnetoelastic plane problems of an infinite soft ferromagnetic strip containing two symmetric edge cracks normal to the boundary are formulated in terms of a singular integral equation. The main purpose of the paper is to investigate the effect of magnetic fields on the stress intensity factors. The solutions of the problems are obtained for a uniform magnetic field normal to the crack surfaces and for uniaxial tension applied to the strip away from the crack region. A strain gage method is also employed in tensile tests to determine the magnetic stress intensity factors. The theoretical results for the plane stress case agree very well with the experimental values.

  297. Analysis of Mode I interlaminar fracture and damage behavior of GFRP woven laminates at cryogenic temperatures 査読有り

    M Sumikawa, Y Shindo, T Takeda, F Narita, S Takano, K Sanada

    JOURNAL OF COMPOSITE MATERIALS 39 (22) 2053-2066 2005年

    出版者・発行元:SAGE PUBLICATIONS LTD

    DOI: 10.1177/0021998305052029  

    ISSN:0021-9983

    詳細を見る 詳細を閉じる

    The interlaminar fracture and damage behavior of glass fiber-reinforced polymer (GFRP) woven laminates at cryogenic temperatures has been investigated theoretically and numerically. The corrected beam theory and finite element analysis (FEA) have been used to calculate the Mode I interlaminar fracture toughness (IFT) of double cantilever beam (DCB) specimens at room temperature, liquid nitrogen temperature (77 K), and liquid helium temperature (4 K). The effect of temperature on the Mode I IFT was investigated. A FEA coupled with damage was also employed to study the damage distributions within the specimen and to examine the effect of damage on the Mode I energy release rate. The corrected beam theory or FEA shows good agreement with the previous experimental compliance of the DCB specimen. The numerical results show that damage causes a decrease in the energy release rate. This work is the first application of failure criteria (Hoffman criterion and maximum strain criterion) to the analysis of the cryogenic behavior of woven laminate DCB specimens.

  298. Three-dimensional thermoelastic analysis of cracked plain weave glass/epoxy composites at cryogenic temperatures 査読有り

    T Takeda, Y Shindo, F Narita

    COMPOSITES SCIENCE AND TECHNOLOGY 64 (15) 2353-2362 2004年11月

    出版者・発行元:ELSEVIER SCI LTD

    DOI: 10.1016/j.compscitech.2004.04.003  

    ISSN:0266-3538

    詳細を見る 詳細を閉じる

    This paper examines the thermo-mechanical behavior of cracked G-11 woven glass/epoxy laminates with temperature-dependent material properties under tension at cryogenic temperatures. Three-dimensional finite elements are employed to model the architecture of the two-layer woven laminates. It is assumed that the cracks are confined to individual fiber bundles oriented transverse to the tensile load direction and span the thickness of the fiber bundles. The effects of residual thermal stresses caused by differences in the coefficients of thermal expansion of the composite constituents, and cracks on the mechanical behavior of two-layer G-11 woven laminates at cryogenic temperatures are explored. Numerical results for Young's modulus, Poisson's ratio, and stress distributions and concentrations are obtained and discussed in detail. (C) 2004 Elsevier Ltd. All rights reserved.

  299. The Planar Crack Problem for a Dielectric Medium in a Uniform Electric Field 査読有り

    Y. Shindo, F. Narita

    Archives of Mechanics 56 (6) 425-441 2004年11月

  300. Electroelastic effect induced by electrode embedded at the interface of two piezoelectric half-planes 査読有り

    F Narita, M Yoshida, Y Shindo

    MECHANICS OF MATERIALS 36 (10) 999-1006 2004年10月

    出版者・発行元:ELSEVIER SCIENCE BV

    DOI: 10.1016/j.mechmat.2003.04.003  

    ISSN:0167-6636

    詳細を見る 詳細を閉じる

    Following the theory of linear piezoelectricity, we consider the static behavior of the elastic and electric variables in the vicinity of an internal electrode embedded at the interface of two dissimilar piezoelectric half-planes. Fourier transforms are used to reduce the mixed boundary value problem to the solution of a pair of dual integral equations. The integral equations are solved exactly, and the displacement and electric potential are expressed in closed form. The solution is also obtained for bonded piezoelectric and elastic half-planes with an electrode embedded at the interface. Numerical values on the stress and electric displacement are obtained, and the results are plotted to display the electroelastic interactions. (C) 2003 Elsevier Ltd. All rights reserved.

  301. Tensile testing and analysis of ferromagnetic elastic strip with a central crack in a uniform magnetic field 査読有り

    Y Shindo, D Sekiya, F Narita, K Hohiguchi

    ACTA MATERIALIA 52 (15) 4677-4684 2004年9月

    出版者・発行元:PERGAMON-ELSEVIER SCIENCE LTD

    DOI: 10.1016/j.actamat.2004.06.029  

    ISSN:1359-6454

    詳細を見る 詳細を閉じる

    The effect of magnetic fields on the fracture mechanics parameters such as the stress intensity factor, energy density, etc., is discussed by analyzing the plane strain and plane stress problems of a soft ferromagnetic strip with a central crack under a uniform magnetic field. The problem of an infinitely long soft ferromagnetic elastic strip with a central crack is formulated by means of integral transforms and reduced to the solution of a Fredholm integral equation of the second kind. Numerical values on the fracture mechanics parameters are obtained. Tensile tests are also conducted on center-cracked soft magnetic plate with strain gage technique, and the numerical predictions for the plane stress case are compared with the test results. Agreement between theory and experiment is fair. (C) 2004 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  302. Finite Element Analysis of Fracture and Polarization Switching Behavior in Modified Small Punch Testing of Piezoelectric Ceramics 査読有り

    Y. Shindo, F. Narita, Y. Magara, M. Karaiwa

    ICTAM04 Abstracts and CD-ROM Proceedings 256-257 2004年8月

  303. Analysis of Tensile Testing of a Soft Ferromagnetic Elastic Strip Containing a Central Crack under a Magnetic Field 査読有り

    D. Sekiya, Y. Shindo, F. Narita, K. Horiguchi

    ICTAM04 Abstracts and CD-ROM Proceedings 262-263 2004年8月

  304. Three-Dimensional Thermoelastic Analysis of Plain Weave Glass/Epoxy Composites with Cracks at Cryogenic Temperatures 査読有り

    T. Takeda, Y. Shindo, F. Narita

    ICTAM04 Abstracts and CD-ROM Proceedings 289-290 2004年8月

  305. Electroelastic Fields Concentrations and Polarization Switching by Circular Electrodes in Piezoelectric Disk Composites 査読有り

    F. Narita, Y. Shindo, M. Karaiwa

    ICTAM04 Abstracts and CD-ROM Proceedings 295 2004年8月

  306. FRACTURE MECHANICS ANALYSIS OF MULTI-LAYER PLAIN WEAVE FABRIC LAMINATES WITH TRANSVERSE CRACKS AT CRYOGENIC TEMPERATURES 査読有り

    Tomo Takeda, Yasuhide Shindo, Fumio Narita

    INTERNATIONAL JOURNAL OF COMPUTATIONAL METHODS 1 (1) 151-169 2004年6月

    出版者・発行元:WORLD SCIENTIFIC PUBL CO PTE LTD

    DOI: 10.1142/S0219876204000046  

    ISSN:0219-8762

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    This paper presents the stress intensity factors for internal and edge cracks in multi-layer glass/epoxy plain weave fabric laminates subjected to uniaxial tension load at cryogenic temperatures. Cracks are considered to have occurred in the transverse fiber bundles. Finite element analysis of the limiting case when the cracks extend to the interfaces between two fiber bundles is carried out. Special singular elements containing the exact stress singularity are used to model the singular stress field near the crack tip. Numerical results for the stress intensity factor at cryogenic temperatures are displayed graphically and discussed in detail.

  307. Electroelastic field concentrations ahead of electrodes in multilayer piezoelectric actuators: experiment and finite element simulation 査読有り

    Y Shindo, M Yoshida, F Narita, K Horiguchi

    JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS 52 (5) 1109-1124 2004年5月

    出版者・発行元:PERGAMON-ELSEVIER SCIENCE LTD

    DOI: 10.1016/j.jumps.2003.09.017  

    ISSN:0022-5096

    詳細を見る 詳細を閉じる

    The effects of applied voltage on the electroelastic field concentrations ahead of electrodes in multilayer piezoelectric actuators were examined in a combined experimental, and numerical investigation. Experiments were performed to measure the strain near internal and surface electrodes at various electrical loading conditions. The finite element method was also used to solve the coupled electro-elastic boundary value problem. The strain, stress and electric displacement concentrations were calculated and a non-linear behavior induced by localized polarization switching was discussed. A comparison of strain concentration was made between experiment and simulation. (C) 2003 Elsevier Ltd. All rights reserved.

  308. Finite element analysis of electric fracture properties in modified small punch testing of piezoceramic plates 査読有り

    Y Magara, F Narita, Y Shindo, M Karaiwa

    JOURNAL OF APPLIED PHYSICS 95 (8) 4303-4309 2004年4月

    出版者・発行元:AMER INST PHYSICS

    DOI: 10.1063/1.1682693  

    ISSN:0021-8979

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    The fracture behavior of a piezoelectric ceramic under applied electric fields has been the subject of recent studies. We have used finite element analysis to study experiments with the modified small punch (MSP) technique. Nonlinear three-dimensional finite element analysis was employed to calculate the MSP energy and maximum strain energy density. The effects of an applied electric field, 180degrees and 90degrees domain switching on the MSP energy, and maximum strain energy density are discussed, and the model predictions are compared with the results of the experiments. The polarization switching zones corresponding to combined mechanical and electrical loads are also obtained. (C) 2004 American Institute of Physics.

  309. Theoretical and experimental determination of magnetic stress intensity factors of a crack in a double cantilever beam specimen 査読有り

    K Yoshimura, Y Shindo, K Horiguchi, F Narita

    FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES 27 (3) 213-218 2004年3月

    出版者・発行元:BLACKWELL PUBLISHING LTD

    DOI: 10.1111/j.1460-2695.2004.00748.x  

    ISSN:8756-758X

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    This paper presents the results of an experimental and theoretical investigation of the magnetic fracture behaviour of double cantilever beam (DCB) specimens. DCB tests were conducted on ferritic stainless steel SUS430 in the bore of a superconducting magnet at room temperature. A simple experimental technique using strain gauges was used to determine the stress intensity factor. The experiments show the predicted increase in the stress intensity factor with increasing magnetic field. The theoretical analysis is based on a beam-plate theory for magnetoelastic interactions in a soft ferromagnetic material. Numerical calculations are carried out, and the stress intensity factor is obtained for several values of magnetic field. A comparison of the stress intensity factor is made between theory and experiment, and the agreement is good for the magnetic field considered.

  310. Stress intensity factors for woven glass/epoxy laminates with cracks at cryogenic temperatures 査読有り

    T Takeda, Y Shindo, F Narita, K Sanada

    MECHANICS OF ADVANCED MATERIALS AND STRUCTURES 11 (2) 109-132 2004年3月

    出版者・発行元:TAYLOR & FRANCIS INC

    DOI: 10.1080/15376490490277312  

    ISSN:1537-6494

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    We investigate the stress intensity factors for several crack configurations in G-11 woven glass/epoxy laminates with temperature-dependent properties under tension at cryogenic temperatures. A state of generalized plane strain is assumed. Cracks are assumed to have occurred in the transverse fiber bundles. Cases of a single stack and doubly-periodic arrays of cracks are considered. The order of stress singularities at the tip of a crack is obtained for the case where the crack is normal to and ends at an interface between two fiber bundles. A finite element method is used to determine the stress intensity factors at the crack tip of two-layered woven laminates. Special singular elements containing the exact stress singularity are placed around the crack tip. Numerical results for the stress intensity factor and the order of stress singularities at cryogenic temperatures are obtained and are presented in a graphical form.

  311. Dynamic antiplane shear of a circular piezoelectric fiber embedded in an elastic matrix with curved interface cracks 査読有り

    K Minamida, F Narita, Y Shindo

    MECHANICS OF ADVANCED MATERIALS AND STRUCTURES 11 (2) 133-150 2004年3月

    出版者・発行元:TAYLOR & FRANCIS INC

    DOI: 10.1080/15376490490277295  

    ISSN:1537-6494

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    Based on the dynamic theory of linear piezoelectricity, we investigated the scattering of horizontally polarized shear waves from a single piezoelectric fiber partially bonded to an elastic matrix. The debonding is assumed to be curved interface cracks with non-contacting faces. The wave function expansion method is employed to reduce the problem to the solution of a pair of dual series equations. The solution of the dual series equations is then expressed in terms of a singular integral equation, introducing a dislocation density function. Numerical results for P7-epoxy and N8-epoxy composites are obtained. The effects of frequency, crack angles, and distributions on the dynamic stress intensity factor, dynamic energy release rate, scattering cross section, and electrical signal are discussed in detail.

  312. 圧電トランスの電気破壊力学解析と分域回転(OS2-2 圧電材料システム,OS2 先端材料システム設計とメゾメカニックス)

    唐岩 賢, 成田 史生, 進藤 裕英

    材料力学部門講演会講演論文集 2004 341-342 2004年

    出版者・発行元:一般社団法人日本機械学会

    DOI: 10.1299/jsmezairiki.2004.0_341  

  313. Double Torsion Testing and Finite Element Analysis for Determining the Electric Fracture Properties o Piezoelctric Ceramics

    唐岩 賢, 進藤 裕英, 成田 史生

    年次大会講演論文集 2004 333-334 2004年

    出版者・発行元:一般社団法人日本機械学会

    DOI: 10.1299/jsmemecjo.2004.1.0_333  

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    This paper presents the results of an experimental and numerical investigation in electric fracture behavior of composite PZT double torsion (DT) specimens. DT tests were conducted on a commercial piezoelectric ceramic bonded between two metals. Fracture loads under different electric fields were obtained from the experiment. Nonlinear three-dimensional finite element analysis was also employed to calculate the energy release rate for DT specimens based on the exact (permeable) and approximate (impermeable) crack models. The effects of applied electric field and polarization switching on the energy release rate are discussed, and the model predictions are compared with the results of the experiments.

  314. Evaluation of Cryogenic Fracture and Damage Properties of GFRP Compact Tension Specimens

    進藤 裕英, 隅川 真由美, 成田 史生, 真田 和昭, 熊谷 進

    年次大会講演論文集 2004 349-350 2004年

    出版者・発行元:一般社団法人日本機械学会

    DOI: 10.1299/jsmemecjo.2004.1.0_349  

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    This paper describes an experimental and analytical study on fracture and damage behavior of GFRP woven laminates at cryogenic temperatures. CT (compact tension) tests were carried out at room temperature, liquid nitrogen temperature (77 K) and liquid helium temperature (4 K) to evaluate the critical values of the fracture mechanics parameters. During the CT tests, AE (acoustic emission) method was implemented. AE signals can identify the critical load at which gross failure occurs. A FEA (finite element analysis) was also done to calculate the fracture mechanics parameters. The failure criteria (Hoffman criterion and maximum strain criterion) or the damage variable based on the continuum damage mechanics was incorporated into the model to interpret the experimental measurements and to study the damage distributions within the specimen. Several methods of calculating J-integral are discussed.

  315. Tensile Deformation and Progressive Failure Behavior of Woven-Fabric GFRP Laminates at Cryogenic Temperatures

    竹田 智, 高野 哲, 進藤 裕英, 成田 史生

    年次大会講演論文集 2004 347-348 2004年

    出版者・発行元:一般社団法人日本機械学会

    DOI: 10.1299/jsmemecjo.2004.1.0_347  

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    This paper focuses on understanding the deformation and progressive failure behavior of glass/epoxy plain weave fabric-reinforced laminates subjected to uniaxial tension load at cryogenic temperatures. Cryogenic tensile tests were conducted on the woven-fabric laminates, and the damage development during loading was characterized by AE (acoustic emission) measurements. A finite element methodology for progressive failure analysis of woven-fabric composite panels was also developed, and applied to simulate "knee" behavior in the stress-strain responses and damage behavior in the tensile test specimens. The effect of strain concentrations due to the fabric architecture on the failure strain of the material was considered by incorporating the SVF (strain variation factor) from meso-scale analysis of a woven-fabric composite unit into the macro-scale analysis of the specimens. A comparison was made between the finite element predictions and the experimental data, and the agreement is good.

  316. Experimental and finite-element analysis of woven glass-cloth/epoxy laminate tensile specimen at room and low temperatures 査読有り

    S Kumagai, Y Shindo, K Horiguchi, F Narita

    MECHANICS OF ADVANCED MATERIALS AND STRUCTURES 11 (1) 51-66 2004年1月

    出版者・発行元:TAYLOR & FRANCIS INC

    DOI: 10.1080/15376490490257666  

    ISSN:1537-6494

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    To evaluate the tensile properties of SL-ES30 glass-cloth/epoxy laminates for superconducting magnets in fusion energy systems, tensile tests were examined both experimentally and analytically. The tensile tests were conducted in accordance with JIS K 7054 at room temperature and liquid nitrogen temperature (77 K). The general specimen geometry was a rectangular dog-bone shape with constant gage length but with each specimen size having a different specimen width. The experimental finding provides the data for analytical modeling. The model utilizes two damage variables that are determined from experimental data. A finite-element method coupled with damage was adopted for the extensional analysis. The effects of temperature, specimen geometry, and gripping method on the tensile properties are examined.

  317. The Thermo-Mechanical Problem of Internal and Edge Cracks in Multi-Layered Woven GFRP Laminates at Cryogenic Temperatures 査読有り

    T. Takeda, Y. Shindo, F. Narita

    Advances in Cryogenic Engineering 50 248-255 2004年

  318. The Thermo-Mechanical Problem of Internal and Edge Cracks in Multi-Layered Woven GFRP Laminates at Cryogenic Temperatures 査読有り

    T. Takeda, Y. Shindo, F. Narita

    Advances in Cryogenic Engineering 50 248-255 2004年

  319. Electroelastic Fields Concentrations and Polarization Switching by Electrodes in Multilayer Piezoelectric Actuators 査読有り

    Y. Shindo, F. Narita, M. Yoshida, K. Horiguchi

    Applied Mechanics in the Americas 10 2004年1月

  320. Tensile deformation and progressive failure behavior of woven-fabric gfrp laminates at cryogenic temperatures 査読有り

    Satoru Takano, Tomo Takeda, Yasuhide Shindo, Fumio Narita

    American Society of Mechanical Engineers, Aerospace Division (Publication) AD 69 395-403 2004年

    出版者・発行元:American Society of Mechanical Engineers (ASME)

    DOI: 10.1115/IMECE2004-60906  

    ISSN:0733-4230

    詳細を見る 詳細を閉じる

    This paper focuses on understanding the deformation and progressive failure behavior of glass/epoxy plain weave fabric-reinforced laminates subjected to uniaxial tension load at cryogenic temperatures. Cryogenic tensile tests were conducted on the woven-fabric laminates, and the damage development during loading was characterized by AE (acoustic emission) measurements. A finite element methodology for progressive failure analysis of woven-fabric composite panels was also developed, and applied to simulate "knee" behavior in the stress-strain responses and damage behavior in the tensile test specimens. The effect of strain concentrations due to the fabric architecture on the failure strain of the material was considered by incorporating the SVF (strain variation factor) from meso-scale analysis of a woven-fabric composite unit into the macro-scale analysis of the specimens. A comparison was made between the finite element predictions and the experimental data, and the agreement is good. Copyright © 2004 by ASME.

  321. Electroelastic field concentration by circular electrodes in piezoelectric ceramics 査読有り

    M Yoshida, F Narita, Y Shindo, M Karaiwa, K Horiguchi

    SMART MATERIALS & STRUCTURES 12 (6) 972-978 2003年12月

    出版者・発行元:IOP PUBLISHING LTD

    DOI: 10.1088/0964-1726/12/6/015  

    ISSN:0964-1726

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    The electroelastic field concentration due to circular electrodes in piezoelectric ceramics has been discussed through theoretical, numerical and experimental characterizations. This paper consists of two parts. In the first part, the problem of a surface electrode attached to a semi-infinite piezoelectric solid was formulated by means of Hankel transforms and the solution was solved exactly. The displacements and electric potential were expressed in closed form. In the second part, finite element analysis was carried out to study electroelastic fields in piezoelectric disks containing circular electrodes of different radii by introducing a model for polarization switching in local areas of electroelastic field concentration. A nonlinear behavior induced by localized polarization switching was observed between the strain and the voltage applied to the electrode. Experiments were also conducted to study the strain state near the electrode tip. Comparison of the predictions by the present model with experimental data is conducted and pertinent conclusions are drawn. This work is the first attempt to obtain nonlinear electroelastic fields around a circular electrode in piezoelectric ceramics and validate the polarization switching model.

  322. Cryogenic Mechanical Response of Multi-Layered Woven-Fabric Glass/Epoxy Laminates with Cracks 査読有り

    T. Takeda, Y. Shindo, F. Narita

    Metals Materials And Processes 15 (3/4) 293-306 2003年12月

  323. Displacement and polarization switching properties of piezoelectric laminated actuators under bending 査読有り

    K Hayashi, Y Shindo, F Narita

    JOURNAL OF APPLIED PHYSICS 94 (7) 4603-4607 2003年10月

    出版者・発行元:AMER INST PHYSICS

    DOI: 10.1063/1.1603963  

    ISSN:0021-8979

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    The displacement and polarization switching properties of piezoelectric laminated actuators have been investigated theoretically, numerically, and experimentally. A laminated beam theory solution is developed for the piezoceramic/metal/piezoceramic actuator, and the effects of electric fields on the displacements of the actuators are analyzed. The mathematical procedure of the present analysis is simple and clear, and the resulting solutions for the displacement of the cantilever laminated beam actuator are highly accurate. A nonlinear three-dimensional finite element analysis is also employed. Bending tests are used to validate the numerical predictions, using laminated actuators made with ferroelectric lead zirconate titanate piezoelectric layers and Fe-48% Ni host material. Good agreement is obtained between the tests and predictions. (C) 2003 American Institute of Physics.

  324. Electroelastic analysis of a piezoelectric cylindrical fiber with a penny-shaped crack embedded in a matrix 査読有り

    S Lin, F Narita, Y Shindo

    INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES 40 (19) 5157-5174 2003年9月

    出版者・発行元:PERGAMON-ELSEVIER SCIENCE LTD

    DOI: 10.1016/S0020-7683(03)00261-0  

    ISSN:0020-7683

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    The electroelastic response of a penny-shaped crack in a piezoelectric cylindrical fiber embedded in an elastic matrix is investigated in this study. Fourier and Hankel transforms are used to reduce the problem to the solution of a pair of dual integral equations. They are then reduced to a Fredholm integral equation of the second kind. Numerical values on the stress intensity factor, energy release rate and energy density factor for piezoelectric composites are obtained to show the influence of applied electric fields. (C) 2003 Elsevier Ltd. All rights reserved.

  325. Electric fracture and polarization switching properties of piezoelectric ceramic PZT studied by the modified small punch test 査読有り

    Y Shindo, F Narita, K Horiguchi, Y Magara, M Yoshida

    ACTA MATERIALIA 51 (16) 4773-4782 2003年9月

    出版者・発行元:PERGAMON-ELSEVIER SCIENCE LTD

    DOI: 10.1016/S1359-6454(03)00303-3  

    ISSN:1359-6454

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    The fracture behavior of a piezoelectric ceramic under applied electric fields has been discussed through experimental and theoretical characterizations. The modified small punch (MSP) tests were performed on a commercial piezoelectric ceramic. The fracture initiation loads under different electric fields were obtained from the experiment. Fracture surface was examined for the MSP specimens to identify the failure mechanisms under high electric fields. A nonlinear three-dimensional finite element analysis was also employed to calculate the fracture deflection and MSP energy. A procedure is presented for determining the fracture and polarization switching properties due to electrical effects by experimental and theoretical means. (C) 2003 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  326. Electroelastic analysis of a penny-shaped crack in a piezoelectric ceramic under mode I loading 査読有り

    S Lin, F Narita, Y Shindo

    MECHANICS RESEARCH COMMUNICATIONS 30 (4) 371-386 2003年7月

    出版者・発行元:PERGAMON-ELSEVIER SCIENCE LTD

    DOI: 10.1016/S0093-6413(03)00031-4  

    ISSN:0093-6413

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    Following the theory of linear piezoelectricity, we consider the electroelastic problem for a piezoelectric ceramic with a penny-shaped crack under mode I loading. The problem is formulated by means of Hankel transform and the solution is solved exactly. The stress intensity factor, energy release rate and energy density factor for the exact and impermeable crack models are expressed in closed form and compared for a P-7 piezoelectric ceramic. Based on current findings, we suggest that the energy release rate and energy density factor criteria for the exact crack model are superior to fracture criteria for the impermeable crack model. (C) 2003 Elsevier Science Ltd. All rights reserved.

  327. Comparison of energy release rate and energy density criteria for a piezoelectric layered composite with a crack normal to interface 査読有り

    S Lin, F Narita, Y Shindo

    THEORETICAL AND APPLIED FRACTURE MECHANICS 39 (3) 229-243 2003年5月

    出版者・発行元:ELSEVIER SCIENCE BV

    DOI: 10.1016/S0167-8442(03)00004-1  

    ISSN:0167-8442

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    A critical comparison of the energy release rate and energy density criteria is made using the example of a piezoelectric layer bonded between two half-spaces of a different elastic solid containing a crack normal to the interfaces. Numerical values of stress intensity factor, energy release rate and energy density factor are presented to exhibit electroelastic interactions. Considered are the exact (permeable) and impermeable crack models. The energy release rate criterion led to negative values which are unphysical. This is consistent with previously published results that seem to contradict with experimental observation related to crack growth enhancement and retardation. The energy density factor always remains positive. This shows that a knowledge of the stress intensity factors alone is not sufficient to explain the behavior of fracture in piezoelectric materials. (C) 2003 Elsevier Science Ltd. All rights reserved.

  328. 1022 き裂を有する強磁性平板の引張試験と磁気弾性解析

    関谷 大輔, 進藤 裕英, 堀口 勝三, 成田 史生

    材料力学部門講演会講演論文集 2003 777-778 2003年

    出版者・発行元:一般社団法人日本機械学会

    DOI: 10.1299/jsmezairiki.2003.0_777  

  329. 652 曲げを受ける圧電積層アクチュエータの変位・分域回転特性

    林 啓輔, 成田 史生, 進藤 裕英

    年次大会講演論文集 2003 167-168 2003年

    出版者・発行元:一般社団法人日本機械学会

    DOI: 10.1299/jsmemecjo.2003.7.0_167  

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    The displacement and polarization switching properties of piezoelectric laminated actuators have been investigated theoretically, numerically and experimentally. A laminated beam theory solution is developed for the piezoceramic/metal/piezoceramic actuator, and the effects of electric fields on the displacements of the actuators are analyzed. A nonlinear three-dimensional finite element analysis is also employed. Bending tests are used to validate the numerical predictions, using laminated actuators made with PZT piezoelectric layers and Fe-48%Ni host material. Good agreement is obtained between the tests and predictions.

  330. Penny-shaped crack in a piezoceramic cylinder under Mode I loading 査読有り

    F Narita, S Lin, Y Shindo

    ARCHIVES OF MECHANICS 55 (3) 275-304 2003年

    出版者・発行元:POLISH ACAD SCIENCES INST FUNDAMENTAL TECHNOL RES

    ISSN:0373-2029

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    THE ELECTROELASTIC response of a penny-shaped crack in a piezoelectric cylinder of finite radius is investigated in this study. Fourier and Hankel transforms axe used to reduce the problem to the solution of a pair of dual integral equations. They are then reduced to a Fredholm integral equation of the second kind; Numerical values of the stress intensity factor, energy release rate and energy density factor for piezoelectric ceramics are obtained to show the influence of applied electrical loads.

  331. Magnetic Stress Intensity Factors for Center-Cracked Plate Specimens Under Tension 査読有り

    K. Horiguchi, Y. Shindo, D. Sekiya, F. Narita

    Mesomechanics of Computation and Design of Use-Specific Materials, Simulation and Fabrication of Advanced Materials with Mesoscopic Structures, Edited by G. C. Sih, S. Sakai, V. E. Panin 348-355 2003年

  332. Impact Response of a Piezoelectric Ceramic Cylinder with a Penny-Shaped Crack 査読有り

    F. Narita, Y. Shindo, S. Lin

    Theoretical and Applied Mechanics 52 153-162 2003年

    DOI: 10.11345/nctam.52.153  

  333. Electroelastic fracture mechanics of piezoelectric ceramics 招待有り 査読有り

    F Narita, Y Shindo, K Horiguchi

    MECHANICS OF ELECTROMAGNETIC MATERIAL SYSTEMS AND STRUCTURES 89-101 2003年

    出版者・発行元:WIT PRESS

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    This paper first develops a theoretical electroelastic fracture mechanics for piezoelectric ceramics. Both analytical and simulation methods axe formulated to determine the effect of electric field on the fracture mechanics parameters such as stress intensity factor, energy release rate and energy density factor for exact and impermeable crack models. Then the results of fracture experiments and corresponding finite element analyses of P-7 piezoelectric ceramic are presented. Finally, the validity of the exact model for predicting the fracture mechanics parameters is evaluated by comparison with experimental results.

  334. Electroelastic bending and polarization switching of piezoelectric laminated actuators 査読有り

    F Narita, Y Shindo, K Hayashi, M Yoshida

    COMPUTATIONAL FLUID AND SOLID MECHANICS 2003, VOLS 1 AND 2, PROCEEDINGS 1471-1474 2003年

    出版者・発行元:ELSEVIER SCIENCE BV

    DOI: 10.1016/B978-008044046-0.50359-6  

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    The static electromechanical response of piezoelectric laminated actuators is examined both theoretically and experimentally. A laminated beam theory solution is developed for the cantilever PZT/metal/PZT actuator, and the effects of electrical load on the displacements of the actuators are analyzed. The mathematical procedure of the present analysis is simple and clear, and the resulting solutions for the displacement of the cantilever laminated beam actuator are highly accurate. A nonlinear three-dimensional finite element model incorporating the polarization switching mechanism with the displacement calculation is also developed. Bending tests are used to validate the theoretical predictions, using laminated actuators made with P-713 piezoceramics and Fe-48%Ni host material. Theoretical predictions of the electromechanical displacement and polarization switching properties are in excellent agreement with measured values.

  335. Electroelastic Fracture Mechanics Analysis of Piezoelectric Ceramic Strip 査読有り

    F. Narita, Y. Shindo, S. Lin

    Theoretical and Applied Mechanics 51 23-34 2002年9月

    DOI: 10.11345/nctam.51.23  

  336. Antiplane shear wave scattering from two curved interface cracks between a piezoelectric fiber and an elastic matrix 査読有り

    Y Shindo, K Minamida, F Narita

    SMART MATERIALS & STRUCTURES 11 (4) 534-540 2002年8月

    出版者・発行元:IOP PUBLISHING LTD

    DOI: 10.1088/0964-1726/11/4/308  

    ISSN:0964-1726

    詳細を見る 詳細を閉じる

    Following the dynamic theory of linear piezoelectricity, we consider the scattering of horizontally polarized shear waves from a single piezoelectric fiber partially bonded to an elastic matrix. The debonding is assumed to be two curved interface cracks with non-contacting. faces, and the two cracks are symmetrically located with respect to the axis of wave propagation. The wavefunction expansion method is used to reduce the problem to the solution of a pair of dual series equations, the solution of which is then expressed in terms of a singular integral equation introducing a dislocation density function. Numerical calculations for P7-epoxy and N8-epoxy composites are carried out, and the effects of frequency, crack angle and piezoelectric material constants on the dynamic stress intensity factor, dynamic energy release rate, scattering cross section and electrical signal are shown graphically.

  337. Thermoelastic analysis of cracked woven GFRP laminates at cryogenic temperatures 査読有り

    T Takeda, Y Shindo, F Narita, S Kumagai

    CRYOGENICS 42 (8) 451-462 2002年8月

    出版者・発行元:ELSEVIER SCI LTD

    DOI: 10.1016/S0011-2275(02)00051-6  

    ISSN:0011-2275

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    We deal with the thermal-mechanical response of multi-layered G-11 woven glass/epoxy laminates with cracks and temperature-dependent properties under tension at liquid helium temperature (4 K). The composite material is assumed to be in generalized plane strain. Cracks are located in the fill fiber bundles and are assumed to span the width of the fill fiber bundles. Finite element model is used to study the influence of residual thermal stresses on the mechanical behavior of multi-layered woven laminates with cracks. Numerical calculations are carried out, and the Young's modulus and stress distributions near the crack tip are shown graphically. (C) 2002 Elsevier Science Ltd. All rights reserved.

  338. Evaluation of Electric Fracture and Deformation Properties of Piezoelectric Ceramics Using Finite Element and Modified Small Punch Test Techniques 査読有り

    Y. Shindo, F. Narita, K. Horiguchi, Y. Magara, M. Yoshida

    Proceedings of International Conference on New Challenges in Mesomechanics Vol. 2 349-355 2002年8月

  339. Evaluation of electric fracture properties of piezoelectric ceramics using the finite element and single-edge precracked-beam methods 査読有り

    Y Shindo, H Murakami, K Horiguchi, F Narita

    JOURNAL OF THE AMERICAN CERAMIC SOCIETY 85 (5) 1243-1248 2002年5月

    出版者・発行元:AMER CERAMIC SOC

    ISSN:0002-7820

    詳細を見る 詳細を閉じる

    Single-edge precracked-beam (SEPB) tests were performed on a commercial lead zirconate titanate (PZT) ceramic. Mechanical loading was applied by the crosshead displacement control of a screw-driven electromechanical test machine. The fracture toughness parameter K-C was determined for various electric fields. A finite element analysis was also done to calculate the total potential energy release rate, mechanical strain energy release rate, and stress intensity factor for three-point flexure piezoceramic specimens with permeable and impermeable cracks under displacement and load control conditions. Numerical investigation and comparison with test data indicate that the energy release rate, upon application of the permeable model, is useful for predicting crack growth in PZT ceramic under electromechanical loading. Based on current findings, we suggest that the energy release rate criteria for the permeable crack are superior to fracture criteria for the impermeable crack.

  340. 401 有限要素法および改良型小型パンチ試験法による圧電セラミックスの破壊・分極回転特性評価

    真柄 安代, 吉田 宗之, 進藤 裕英, 成田 史生, 堀口 勝三

    年次大会講演論文集 2002 1-2 2002年

    出版者・発行元:一般社団法人日本機械学会

    DOI: 10.1299/jsmemecjo.2002.2.0_1  

    詳細を見る 詳細を閉じる

    The fracture behavior of a piezoelectric ceramic under applied electric fields has been discussed through experimental and theoretical characterizations. The modified small punch (MSP) tests were performed on a commercial PZT ceramic. The fracture initiation loads under different electric fields are obtained from the experiment. A nonlinear finite element analysis was also employed to calculate the deflection and MSP energy. An expression is presented for determining the fracture properties due to electrical effects by expreimental and theoretical means.

  341. Scattering of Antiplane Shear Waves by a Circular Piezoelectric Inclusion Embedded in a Piezoelectric Medium Subjected to a Steady-State Electrical Load 査読有り

    Y. Shindo, H. Moribayashi, F. Narita

    ZAMM 82 (1) 43-49 2002年

    DOI: 10.1002/1521-4001(200201)82:1<43::AID-ZAMM43>3.0.CO;2-Z  

  342. A Circular Piezoelectric Inclusion Embedded in an Elastic Matrix with Two Curved Interface Cracks under Dynamic Antiplane Shear 査読有り

    Y. Shindo, K. Minamida, F. Narita

    Applied Mechanics in the Americas 9 89-92 2002年

  343. Electroelastic Analysis of a Long Circular Piezoelectric Cylinder with a Penny-Shaped Crack 査読有り

    F. Narita, S. Lin, Y. Shindo

    Applied Mechanics in the Americas 9 329-332 2002年

  344. Transient thermal-mechanical response of glass-fiber reinforced plastics at low temperatures 査読有り

    Y Shindo, F Narita

    ACTA MECHANICA 157 (1-4) 159-174 2002年

    出版者・発行元:SPRINGER-VERLAG WIEN

    DOI: 10.1007/BF01182161  

    ISSN:0001-5970

    詳細を見る 詳細を閉じる

    We consider the transient thermal-mechanical behavior of glass-fiber reinforced plastics with temperature-dependent properties at low temperatures. The layered composite is made of a layer bonded between two layers of different physical properties. and it is suddenly cooled on the surfaces. The composite material in generalized plane strain is assumed. The thermal and elastic properties as functions of temperature are compiled from the experimental data. Numerical results presented, include the transient temperature distribution and the thermal-mechanical stress.

  345. Single-Edge Precracked Beam Test and Electric Fracture Mechanics Analysis for Piezoelectric Ceramics 査読有り

    Y. Shindo, K. Horiguchi, H. Murakami, F. Narita

    Proceedings of SEPI 4235 311-320 2001年12月

    DOI: 10.1117/12.420894  

  346. Circular Inclusion Problem in Dynamic Antiplane Piezoelectricity 査読有り

    F. Narita, Y. Shindo, H. Moribayashi

    Proceedings of SPIE 4235 69-78 2001年12月

    DOI: 10.1117/12.420884  

  347. Mode I crack growth rate for yield strip model of a narrow piezoelectric ceramic body 査読有り

    F Narita, Y Shindo

    THEORETICAL AND APPLIED FRACTURE MECHANICS 36 (1) 73-85 2001年7月

    出版者・発行元:ELSEVIER SCIENCE BV

    DOI: 10.1016/S0167-8442(01)00058-1  

    ISSN:0167-8442

    詳細を見る 詳細を閉じる

    A crack growth rate equation is found for a finite crack in a narrow transversely isotropic piezoelectric ceramic body under tensile loading. Use is made of the yield strip model. The crack is situated in the mid-plane and is parallel to the edges of the body. Integral transforms are applied to reduce the problem to a Fredholm integral equation of the second kind. The accumulated plastic displacement criterion is applied to crack growth at low stress levels. This results in a small crack growth rate equation with fourth-power stress intensity factor dependence. Numerical examples are given for piezoelectric ceramics and the crack growth rates are plotted as a function of body height to crack length ratio for various values of the electrical loads. (C) 2001 Elsevier Science Ltd. All rights reserved.

  348. K-0836 2個の界面き裂を有する圧電繊維複合材料の面外せん断波散乱(S09-3 界面の特異性)(S09 特異点解析と強度評価への適用)

    南田 敬一, 進藤 裕英, 成田 史生

    年次大会講演論文集 1 451-452 2001年

    出版者・発行元:一般社団法人日本機械学会

    DOI: 10.1299/jsmemecjo.I.01.1.0_451  

    詳細を見る 詳細を閉じる

    Following the dynamic theory of linear piezoelectricity, we consider the scattering of horizontally polarized shear waves from a single piezoelectric fiber partially bonded to an elastic matrix. The debonding is assumed to be two curved interface cracks with non-contacting faces, and the two cracks are symmetrically located with respect to the axis of wave propagation. Wave function expansion method is used to reduce the problem to the solution of a pair of dual series equations, the solution of which is then expressed in terms of a singular integral equation introducing a dislocation density function. Numerical calculations for P7-epoxy and N8-epoxy composites are carried out, and the effects of frequency, crack angle and piezoelectric material constants on the scattering cross section, dynamic stress intensity factor and dynamic energy release rate are shown graphically.

  349. Scattering of Antiplane Shear Waves from a Partially Debonded Piezoelectric Fiber 査読有り

    Y. Shindo, F. Narita, H. Moribayashi, K. Minamida

    Theoretical and Applied Mechanics 50 183-191 2001年

    DOI: 10.11345/nctam.50.183  

  350. Thermal-Mechanical Response of Cracked Woven Glass/Epoxy Laminates in a Tension Field at Low Temperature 査読有り

    T. Takeda, Y. Shindo, S. Kumagai, F. Narita, K. Horiguchi

    Physical Mesomechanics 4 (4) 97-104 2001年

  351. Evaluation of Single-Edge Precracked Beam Specimens of Piezoelectric Ceramics 査読有り

    Y. Shindo, M. Oka, K. Horiguchi, F. Narita

    Role of Mechanics for Development of Science and Technology Vol. II 863-872 2000年6月

  352. Electroelastic Analysis of a Piezoelectric Ceramic Strip with a Central Crack 査読有り

    Y. Shindo, K. Watanabe, F. Narita

    Int. J. Engng Sci. 38 (1) 1-19 2000年

    DOI: 10.1016/S0020-7225(99)00015-4  

  353. Scattering of antiplane shear waves by a finite crack in piezoelectric laminates 査読有り

    F Narita, Y Shindo

    ACTA MECHANICA 134 (1-2) 27-43 1999年

    出版者・発行元:SPRINGER-VERLAG WIEN

    DOI: 10.1007/BF01170302  

    ISSN:0001-5970

    詳細を見る 詳細を閉じる

    Following the dynamic theory of linear piezoelectricity, we consider the scattering of horizontally polarized shear waves by a finite crack in a composite laminate containing a piezoelectric layer. The piezoelectric layer is bonded between two half-spaces of a different elastic solid. The crack is normal to the interfaces and is placed at an equal distance away from them. Both cases of a partially broken layer and a completely broken layer are studied. Fourier transforms are used to reduce the problem to the solution of a pair of dual integral equations. The solution of the dual integral equations is then expressed in terms of a singular integral equation. The propagation of symmetric first mode is studied numerically, and the dynamic stress intensity factor and the dynamic energy release rate are obtained for some piezoelectric laminates.

  354. Fatigue crack propagation in a piezoelectric ceramic strip subjected to mode III loading 査読有り

    F Narita, Y Shindo

    ACTA MECHANICA 137 (1-2) 55-63 1999年

    出版者・発行元:SPRINGER-VERLAG WIEN

    ISSN:0001-5970

    詳細を見る 詳細を閉じる

    Following the theory of linear piezoelectricity, a forth-power stress intensity factor crack growth equation in an orthotropic piezoelectric ceramic strip is developed under mode III loading. The crack is situated symmetrically and oriented in a direction parallel to the edges of the strip. Dugdale's assumption regarding the plastic zone in metals is applied to estimate the effects of yield around the crack tips. Fourier transforms are used to reduce the electroelastic problem to one involving the numerical solution of a Fredholm integral equation of the second kind. A direct approach based on the accumulated plastic displacement criterion for crack propagation is used to develop the equation to predict the fatigue crack growth. Graphical results showing the effect of electroelastic interactions on the fatigue crack growth rate are presented.

  355. Impact response of a finite crack in an orthotropic piezoelectric ceramic 査読有り

    Y Shindo, F Narita, E Ozawa

    ACTA MECHANICA 137 (1-2) 99-107 1999年

    出版者・発行元:SPRINGER-VERLAG WIEN

    ISSN:0001-5970

    詳細を見る 詳細を閉じる

    The transient dynamic stress intensity factor and dynamic energy release rate were determined for a cracked piezoelectric ceramic under normal impact in this study. A plane step pulse strikes the crack and stress wave diffraction takes place. Laplace and Fourier transforms are employed to reduce the transient problem to the solution of a pair of dual integral equations in the Laplace transform plane. The solution of the dual integral equations is then expressed in terms of a Fredholm integral equation of the second kind. A numerical Laplace inversion technique is used to compute the values of the dynamic stress intensity factor and the dynamic energy release rate for some piezoelectric ceramics, and the results are graphed to display the electroelastic interactions.

  356. The Interface Crack Problem for Bonded Piezoelectric and Orthotropic Layers under Antiplane Shear Loading 査読有り

    F. Narita, Y. Shindo

    Int. J. Fract. 98 (1) 87-101 1999年

    DOI: 10.1023/A:1018755614151  

  357. Fatigue Crack Propagation of a Finite Crack in a Piezoelectric Ceramic Strip under Tension Load 査読有り

    Y. Shindo, F. Narita

    Applied Mechanics in the Americas (7) 643-646 1999年1月

  358. Anti-plane shear crack in a piezoelectric layer bonded to dissimilar half spaces 査読有り

    F Narita, Y Shindo, K Watanabe

    JSME INTERNATIONAL JOURNAL SERIES A-SOLID MECHANICS AND MATERIAL ENGINEERING 42 (1) 66-72 1999年1月

    出版者・発行元:JAPAN SOC MECHANICAL ENGINEERS

    DOI: 10.1299/jsmea.42.66  

    ISSN:1340-8046

    詳細を見る 詳細を閉じる

    Following the theory of linear piezoelectricity, we consider the electroelastic problem for a piezoelectric layer with a crack bonded to two elastic half planes under antiplane shear loading. The crack parallel to the interfaces is in the mid-plane of the piezoelectric layer. Fourier transforms are used to reduce the problem to the solution of a pair of dual integral equations. The solution of the dual integral equations is then expressed in terms of a Fredholm integral equation of the second kind. Numerical values of the stress intensity factor for some piezoelectric laminates are obtained,and the results are plotted to display the electroelastic interactions.

  359. Layered piezoelectric medium with interface crack under anti-plane shear 査読有り

    F Narita, Y Shindo

    THEORETICAL AND APPLIED FRACTURE MECHANICS 30 (2) 119-126 1998年10月

    出版者・発行元:ELSEVIER SCIENCE BV

    DOI: 10.1016/S0167-8442(98)00048-2  

    ISSN:0167-8442

    詳細を見る 詳細を閉じる

    The theory of linear piezoelectricity is applied to solve the anti-plane shear problem of a piezoelectric layer sandwiched by two dissimilar homogeneous materials with a crack at the interface. Both mechanical and electrical loads are applied to the piezoelectric laminate. By the use of Fourier transforms, the mixed boundary value problem is reduced to a singular integral equation which is solved numerically to determine the stress intensity factors for several layered piezoelectric media, and the results are presented in graphical form. (C) 1998 Elsevier Science Ltd. All rights reserved.

  360. Anti-plane shear crack growth rate of piezoelectric ceramic body with finite width 査読有り

    F Narita, Y Shindo

    THEORETICAL AND APPLIED FRACTURE MECHANICS 30 (2) 127-132 1998年10月

    出版者・発行元:ELSEVIER SCIENCE BV

    DOI: 10.1016/S0167-8442(98)00049-4  

    ISSN:0167-8442

    詳細を見る 詳細を閉じる

    The theory of linear piezoelectricity is applied to develop an anti-plane crack growth rate equation of a finite crack in a piezoelectric ceramic body with finite width. Plastic zone is assumed to be confined to a sheet ahead of both crack edges similar to the strip model for in-plane loading. The procedure consists of reducing a system of dual integral equations to a Fredholm integral equation of the second kind. The accumulated plastic displacement criterion is used for developing a solution for the crack growth rate. Numerical values of crack growth rate are obtained and the results are displayed graphically to exhibit the electroelastic interactions. (C) 1998 Elsevier Science Ltd. All rights reserved.

  361. Dynamic anti-plane shear of a cracked piezoelectric ceramic 査読有り

    F Narita, Y Shindo

    THEORETICAL AND APPLIED FRACTURE MECHANICS 29 (3) 169-180 1998年7月

    出版者・発行元:ELSEVIER SCIENCE BV

    DOI: 10.1016/S0167-8442(98)00028-7  

    ISSN:0167-8442

    詳細を見る 詳細を閉じる

    The dynamic theory of antiplane piezoelectricity is applied to solve the problem of a line crack subjected to horizontally polarized shear waves in an arbitrary direction. The problem is formulated by means of integral transforms and reduced to the solution of a Fredholm integral equation of the second kind. The path-independent integral G is extended here to include piezoelectric effects, and is evaluated at the crack tip to obtain the dynamic energy release rate. Numerical calculations are carried out for the dynamic stress intensity factor and energy release rate. The material is piezoelectric ceramic. (C) 1998 Elsevier Science Ltd. All rights reserved.

  362. Dynamic bending of a symmetric piezoelectric laminated plate with a through crack 査読有り

    Y Shindo, W Domon, F Narita

    THEORETICAL AND APPLIED FRACTURE MECHANICS 28 (3) 175-182 1998年2月

    出版者・発行元:ELSEVIER SCIENCE BV

    DOI: 10.1016/S0167-8442(98)00003-2  

    ISSN:0167-8442

    詳細を見る 詳細を閉じる

    The dynamic theory of linear piezoelectricity is applied to analyze the scattering of time harmonic flexural waves by a through crack in a symmetric piezoelectric laminated plate subjected to electric field loading. An incident wave giving rise to moments symmetric about the crack plane is considered. Piezoelectric layers are added to the upper and lower surfaces. Classical lamination theory is extended to include dynamic piezoelectric effects. Fourier transforms are used to reduce the problem to the solution of a pair of dual integral equations, the solution of which is then expressed in terms of a Fredholm integral equation of the second kind. The dynamic moment intensity factor vs. frequency is computed and the influence of the electric field on the normalized values is displayed graphically. (C) 1998 Elsevier Science Ltd. All rights reserved.

  363. Scattering of Love waves by a surface-breaking crack in piezoelectric layered media 査読有り

    F Narita, Y Shindo

    JSME INTERNATIONAL JOURNAL SERIES A-SOLID MECHANICS AND MATERIAL ENGINEERING 41 (1) 40-48 1998年1月

    出版者・発行元:JAPAN SOC MECHANICAL ENGINEERS

    DOI: 10.1299/jsmea.41.40  

    ISSN:1340-8046

    詳細を見る 詳細を閉じる

    Based on the dynamic theory of linear piezoelectricity, we investigate the scattering of Love waves by a surface-breaking crack in a layered piezoelectric solid. The piezoelectric layer is perfectly bonded to a half-space of a different elastic solid and the crack is normal to the free surface. Both cases of a partially broken layer and a completely broken layer are studied. By the use of Fourier transform techniques, the mixed boundary value problem is reduced to a singular integral equation. The singular integral equation is solved numerically to determine the dynamic stress intensity factor and the dynamic energy release rate as a function of a dimensionless frequency for various ratios of crack depth to layer thickness, and the results are presented in graphical form.

  364. Electroelastic Analysis of Piezoelectric Ceramics with Surface Electrodes 査読有り

    Y. Shindo, F. Narita, H. Sosa

    Int. J. Engng Sci. 36 (9) 1001-1009 1998年

    DOI: 10.1016/S0020-7225(98)00007-X  

  365. Electroelastic Analysis of Fatigue Crack Growth in a Piezoelectric Ceramic Under Longitudinal Shear 査読有り

    F. Narita, Y. Shindo

    Proceedings of the Japan-France Seminar on Intelligent Materials and Structures 149-158 1997年10月

  366. The Scattering of Flexural Waves of a Symmetric Piezoelectric Laminated Plate with a Through Crack 査読有り

    Y.Shindo, W.Domon, F.Narita

    Proceedings of the International Society for Optical Engineering 608-618 1997年3月

  367. Singular stress and electric fields of a piezoelectric ceramic strip with a finite crack under longitudinal shear 査読有り

    Y Shindo, K Tanaka, F Narita

    ACTA MECHANICA 120 (1-4) 31-45 1997年

    出版者・発行元:SPRINGER-VERLAG WIEN

    ISSN:0001-5970

    詳細を見る 詳細を閉じる

    Following the theory of linear piezoelectricity, we consider the problem of determining the singular stress and electric fields in an orthotropic piezoelectric ceramic strip containing a Griffith crack under longitudinal shear. The crack is situated symmetrically and oriented in a direction parallel to the edges of the strip. Fourier transforms are used to reduce the problem to the solution of a pair of dual integral equations. The solution of the dual integral equations is then expressed in terms of a Fredholm integral equation of the second kind. Numerical values on the stress intensity factor and the energy release rate for piezoelectric ceramics are obtained, and the results are graphed to display the influence of the electric field.

  368. Bending of a Symmetric Piezothermoelastic Laminated Plate with a Through Crack 査読有り

    Y. Shindo, W. Domon, F. Narita

    Archives of Mechanics 49 (2) 403-412 1997年

  369. Diffraction of Antiplane Shear Waves by a Finite Crack in an Orthotropic Piezoelectric Ceramic Strip 査読有り

    F. Narita, Y. Shindo

    Theoretical and Applied Mechanics 46 139-149 1997年

  370. Electroelastic intensification near anti-plane shear crack in orthotropic piezoelectric ceramic strip 査読有り

    Y Shindo, F Narita, K Tanaka

    THEORETICAL AND APPLIED FRACTURE MECHANICS 25 (1) 65-71 1996年4月

    出版者・発行元:ELSEVIER SCIENCE BV

    DOI: 10.1016/0167-8442(96)00008-0  

    ISSN:0167-8442

    詳細を見る 詳細を閉じる

    The theory of linear piezoelectricity is applied to solve the antiplane electroelastic problem of an orthotropic piezoelectric ceramic strip with a finite crack, which is situated symmetrically and oriented in a direction normal to the edges of the strip. Fourier transforms are used to reduce the problem to the solution of a pair of dual integral equations. They are then reduced to a Fredholm integral equation of the second kind. Numerical values on the stress intensity factor and the energy release rate for some piezoelectric ceramics are obtained and the results are displayed numerically to exhibit the electroelastic interactions.

  371. Diffraction of an Antiplane Shear Wave by a Finite Crack in an Orthotropic Piezoelectric Ceramic 査読有り

    Y. Shindo, F. Narita

    ASCE Engineering Mechanics, Proceedings of 10th Conference 1 577-580 1995年5月

︎全件表示 ︎最初の5件までを表示

MISC 84

  1. 炭素繊維強化圧電複合材料の開発と振動発電・蓄電によるワイヤレス情報通信

    栗田 大樹, 王 真金, 余 瑶楠, 成田 史生

    クリーンエネルギー / クリーンエネルギー編集委員会 編 32 (11) 41-44 2023年11月

    出版者・発行元:日本工業出版

    ISSN:0918-7510

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    クリーンエネルギー 32 (11) 2023年

    ISSN:0918-7510

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    栗田大樹, Wang Zhenjin, 堀雅敏, 清水紀弘, 成田史生

    繊維学会誌 79 (7) 2023年

    ISSN:0037-9875

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    成田史生, 王 真金, 栗田大樹

    バムサジャーナル 35 (1) 5-9 2023年1月

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    王 真金, 成田史生

    日本複合材料学会誌 49 (1) 13-19 2023年1月

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    小山毅士, 栗田大樹, 成田史生, シャフロン ローラン, デズルス オリビエ, アンドリュー ジェローム

    粉体粉末冶金協会講演大会(Web) 2022 2022年

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    材料とプロセス(CD-ROM) 35 (2) 2022年

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    久保田勇希, 高石佳, 栗田大樹, 成田史生, 中里亜紀子, 山本研吾

    日本複合材料合同会議(Web) 12th 2021年

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    コンバーテック 49 (6) 2021年

    ISSN:0911-2316

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    成田史生

    まてりあ 59 (1) 16-20 2020年1月

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    日本機械学会年次大会講演論文集(CD-ROM) 2019 2019年

    ISSN:2424-2667

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    成田 史生

    パリティー 34 (1) 25-27 2019年1月

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    成田 史生

    パリティー 33 (11) 46-49 2018年11月

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    日本機械学会機械材料・材料加工技術講演会論文集(CD-ROM) 26th 2018年

    ISSN:2424-287X

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    クリーンエネルギー 26 (5) 35-39 2017年5月

    出版者・発行元:日本工業出版

    ISSN:0918-7510

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    成田史生

    精密工学会誌 83 (5) 411-414 2017年5月

    出版者・発行元:精密工学会

    DOI: 10.2493/jjspe.83.411  

    ISSN:0912-0289

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    金属 86 (9) 27-33 2016年9月

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    成田史生

    スマートプロセス学会誌 5 (1) 3-8 2016年1月

    出版者・発行元:高温学会

    DOI: 10.7791/jspmee.5.3  

    ISSN:2186-702X

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    M&M材料力学カンファレンス 2015 "OS1509-289-1"-"OS1509-289-2" 2015年11月21日

    出版者・発行元:一般社団法人日本機械学会

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    This paper studies the vibration energy harvest and response characteristics of poled barium titanate (BT) unimorph cantilevers both analytically and experimentally. The unimorph cantilever consists of the BT layer and Cu shim, and the BT layer has sensing, grounding and driving electrodes. The output voltage of the cantilever excited by bending vibration was predicted by three dimensional finite element analysis (FEA). The output voltage was also measured, and a comparison was made between prediction and experiment. The effects of sensing electrode geometry and load resistance on the dynamic electromechanical fields and output power were then discussed in detail.

  21. GS0402-157 CNT分散ポリマー接着層を有するCFRP継手のモードI破壊・電気抵抗挙動

    竹田 智, 成田 史生, 鹿内 公詞

    M&M材料力学カンファレンス 2015 "GS0402-157-1"-"GS0402-157-2" 2015年11月21日

    出版者・発行元:一般社団法人日本機械学会

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    This paper studies the Mode I fracture behavior and crack monitoring of bonded carbon fiber reinforced polymer (CFRP) composite joints with carbon nanotube (CNT)-based polymer adhesive layer. Mode I fracture tests were carried out with double cantilever beam (DCB) bonded joint specimens consisting of woven carbon/epoxy composite adherends and CNT-based epoxy adhesives, and the critical energy release rate at the onset of crack growth, i.e., fracture toughness, was evaluated. The electrical resistance of the bonded joint specimens was also monitored during the tests. An analytical model based on the electrical conduction mechanism of CNT-based polymers was employed to describe the electrical resistance change due to crack propagation in the bonded joint specimens, and a good correlation was obtained between the predicted and measured results.

  22. 158 チタン酸バリウム多結晶の弾性・圧電定数に及ぼす結晶粒径・酸素欠陥密度の影響に関するフェーズフィールドシミュレーション

    小林 拓矢, 成田 史生

    計算力学講演会講演論文集 2015 (28) "158-1"-"158-2" 2015年10月10日

    出版者・発行元:一般社団法人日本機械学会

    ISSN:1348-026X

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    This work investigates the electromechanical response of poled barium titanate (BaTiO_3) polycrystals with oxygen vacancies at room temperature. A phase field model is developed for ferroelectric polycrystals, coupled with the time-dependent Ginzburg-Landau theory and the oxygen vacancies diffusion, to demonstrate the interaction between oxygen vacancies and domain evolutions. To generate grain structures, the phase field model for grain growth is also employed. The strain vs stress curve and strain vs electric field curve are computed, and the effects of grain size and oxygen vacancy density on the elastic and piezoelectric properties of the BaTiO_3 polycrystals are discussed.

  23. J0610103 交流電場下における燃料インジェクター用多層圧電アクチュエータの高温電気力学応答

    成田 史生, 進藤 裕英

    年次大会 : Mechanical Engineering Congress, Japan 2015 "J0610103-1"-"J0610103-2" 2015年9月13日

    出版者・発行元:一般社団法人日本機械学会

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    This paper examines theoretically and experimentally the dynamic electromechanical response of multilayer piezoelectric actuators for fuel injectors at high temperatures. A phenomenological model of depolarization at high temperatures was used, and the temperature dependent piezoelectric coefficients were obtained. The high temperature electromechanical fields of the multilayer piezoelectric actuators under AC electric fields were then calculated by the finite element method. In addition, test data on the electric field induced strain at high temperatures, which verify the model, were presented.

  24. Cryomechanics and crack behaviour of woven polymer matrix composites

    Yasuhide Shindo, Tomo Takeda, Fumio Narita

    Computational and Experimental Methods in Structures 6 159-178 2015年

    出版者・発行元:World Scientific Publishing Co. Pte Ltd

    DOI: 10.1142/9781783266180_0005  

    ISSN:2044-9283

  25. G0310903 磁場内におけるき裂を有する超磁歪材料の3点曲げ破壊挙動([G031-09]材料力学部門一般セッション:実構造・応用,材料力学部門)

    鹿内 公詞, 進藤 裕英, 成田 史生, 森 孝太郎

    年次大会 : Mechanical Engineering Congress, Japan 2014 "G0310903-1"-"G0310903-3" 2014年9月7日

    出版者・発行元:一般社団法人日本機械学会

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    We present theoretical and experimental results on the fracture behavior of single-edge precracked giant magnetostrictive materials under magnetic fields. The crack was created normal to the direction of easy magnetization. Three-point bending fracture tests were carried out, and the fracture loads were measured. Plane strain finite element analysis was also performed, and the energy release rate was calculated. The effect of magnetic field on the energy release rate and apparent fracture toughness (critical energy release rate obtained using the fracture load) was then discussed.

  26. 616 極低温における中央き裂を有する圧電セラミックスのモードIエネルギー解放率に及ぼす電場・分極の影響(GS03-4 材料力学)

    加藤 大樹, 進藤 裕英, 成田 史生

    講演論文集 2014 (51) "616-1"-"616-2" 2014年3月1日

    出版者・発行元:一般社団法人日本機械学会

  27. 121 極低温における織物ガラス-エポキシ積層材料の混合モードII/III層間はく離疲労き裂進展

    竹田 智, 進藤 裕英, 成田 史生

    講演論文集 2014 (49) 43-44 2014年

    出版者・発行元:一般社団法人日本機械学会

  28. Interlaminar delamination fracture and fatigue of woven glass fiber reinforced polymer composite laminates at cryogenic temperatures

    Yasuhide Shindo, Tomo Takeda, Fumio Narita

    Polymers at Cryogenic Temperatures 9783642353352 115-125 2013年11月1日

    出版者・発行元:Springer-Verlag Berlin Heidelberg

    DOI: 10.1007/978-3-642-35335-2_5  

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    This chapter describes the results of our studies on the interlaminar delamination fracture and fatigue of woven glass fiber reinforced polymer composite laminates under Mode I, Mode II, and Mode III loadings at cryogenic temperatures. Delamination fracture tests were carried out at cryogenic temperatures, and the critical energy release rate at the onset of delamination propagation, i.e., fracture toughness, was evaluated based on a finite element analysis coupled with damage. In addition, cryogenic fatigue delamination tests were performed, in order to obtain the delamination growth rate as a function of the range of the energy release rate. After the tests, fractographic observations were made to assess the delamination mechanisms at cryogenic temperatures.

  29. 206 高速引張を受けるき裂を有するカーボンナノチューブ-ポリマー複合材料の破壊・電気抵抗挙動(材料力学II)

    竹田 智, 進藤 裕英, 成田 史生

    日本機械学会東北支部秋季講演会講演論文集 2013 (49) 41-42 2013年9月20日

    出版者・発行元:一般社団法人日本機械学会

  30. 119 集中荷重を受ける超磁歪/圧電積層カンチレバーの感知・応答特性(材料力学I,一般講演)

    森 孝太郎, 進藤 裕英, 成田 史生

    講演論文集 2013 (48) 40-41 2013年3月15日

    出版者・発行元:一般社団法人日本機械学会

  31. 118 交流電場下における片持ち超磁歪/圧電積層材料の動的曲げ(フェロー賞候補対象講演IV)

    森 孝太郎, 進藤 裕英, 成田 史生

    日本機械学会東北支部秋季講演会講演論文集 2012 (48) 40-41 2012年9月22日

    出版者・発行元:一般社団法人日本機械学会

  32. 139 き裂を有する朱子織炭素繊維強化プラスチック複合材料の極低温・引張に関する三次元熱弾性解析(材料力学I,一般講演)

    竹田 智, 進藤 裕英, 成田 史生

    講演論文集 2012 (47) 84-85 2012年3月13日

    出版者・発行元:一般社団法人日本機械学会

  33. G030081 カーボンナノチューブ分散ポリマーコンポジットの導電率([G03008]材料力学部門一般セッション(8):材料の電気的特性)

    黒沼 遊, 竹田 智, 進藤 裕英, 成田 史生

    年次大会 : Mechanical Engineering Congress, Japan 2011 "G030081-1"-"G030081-3" 2011年9月11日

    出版者・発行元:一般社団法人日本機械学会

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    In this research, we investigate both analytically and experimentally the electrical properties of carbon nanotube (CNT)-based polymer composites. An analytical model was developed to predict the electrical conductivity of CNT-based composites. The micro/nanoscale structures of the nanocomposites and the electrical tunneling effect due to the matrix material between CNTs were incorporated within the model. Electrical conductivity measurements were also performed on CNT/polycarbonate composites to identify the dependence of their electrical transport characteristics on the nanotube content. The analytical predictions were compared with the experimental data, and a good correlation was obtained between the predicted and measured results.

  34. 123 極低温における織物ガラス-エポキシ積層材料の混合モードI/IIはく離疲労き裂進展(材料力学II,一般講演)

    三浦 正哉, 進藤 裕英, 竹田 智, 成田 史生

    講演論文集 2011 (46) 50-51 2011年3月15日

    出版者・発行元:一般社団法人日本機械学会

  35. 212 ハイブリッド積層材料の極低温層間せん断強度特性に及ぼす損傷の影響(OS2-3 先端材料システムの力学とメゾスケールモデリング)

    三浦 正哉, 進藤 裕英, 竹田 智, 成田 史生

    M&M材料力学カンファレンス 2010 293-294 2010年10月9日

    出版者・発行元:一般社団法人日本機械学会

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    This paper presents the expenniental and numerical characterization of the interlaminar shear failure of hybrid composite laminates at cryogenic temperatures. Cryogenic short beam shear tests were performed on hybrid laminates consisting of woven glass fiber reinforced polymer (GFRP) composites and polyimide films to evaluate their interlaminar shear strength. Microscopic observations of damage accumulation and failure mechanisms were also made on failed specimens. In addition, a progressive damage analysis was conducted to predict the initiation and growth of damage in the specimens, and the interlaminar shear strength was determined from the maximum shear stress in the failure region The damage effect on the interlaminar shear properties of hybrid laminates at cryogenic temperatures was examined based on the experimental and numerical results.

  36. 214 交流電場下における1-3圧電/ポリマーコンポジットの動的特性と電気力学場(OS2-4 先端材料システムの力学とメゾスケールモデリング)

    成田 史生, 進藤 裕英

    M&M材料力学カンファレンス 2010 297-298 2010年10月9日

    出版者・発行元:一般社団法人日本機械学会

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    This paper studies the dynamic electromechanical response of 1-3 piezoelectric/polymer composites under alternating current (AC) electric fields. The piezocomposites contain square or circular piezoelectric rods in an epoxy matrix. Experiments were conducted to measure the electrical impedance and phase angle at various frequency, using the device specimen of the 1-3 piezocomposites. Three dimensional finite element analysis was also employed to calculate the frequency characteristics, and a comparison was made between simulation and experiment. The dynamic electromechanical fields in the 1-3 piezocomposites were then discussed in detail.

  37. 702 有孔試験片による織物GFRP積層材料の極低温引張強度評価(材料・設計(4))

    新藤 裕英, 渡邉 慎也, 竹田 智, 成田 史生, 松田 拓也, 八巻 悟

    日本機械学会東北支部秋季講演会講演論文集 2010 (46) 195-196 2010年9月24日

    出版者・発行元:一般社団法人日本機械学会

  38. 131 極低温におけるき裂を有する多層朱子織炭素繊維強化プラスチック積層材料の特異応力場(材料力学I,一般講演)

    渡邉 慎也, 進藤 裕英, 竹田 智, 成田 史生

    講演論文集 2010 (45) 64-65 2010年3月12日

    出版者・発行元:一般社団法人日本機械学会

  39. ショートビーム試験による絶縁材料システムの極低温層間せん断強度評価

    三浦 正哉, 進藤 裕英, 竹田 智, 成田 史生, 渡邉 慎也, 小泉 徳潔, 出崎 亮, 奥野 清

    低温工学・超電導学会講演概要集 = Meetings of Cryogenics and Superconductivity 81 226-226 2009年11月18日

    ISSN:0919-5998

  40. 407 極低温・強砥場下における準安定オーステナイト系ステンレス鋼の疲労き裂進展挙動(材料力学(2))

    進藤 裕英, 竹田 智, 成田 史生

    日本機械学会東北支部秋季講演会講演論文集 2009 (45) 103-104 2009年9月26日

    出版者・発行元:一般社団法人日本機械学会

  41. OS0408 電場下におけるき裂を有する圧電セラミックスの三点曲げによる遅れ破壊・局所分極回転(先端材料システムの力学とメゾスケールモデリング,オーガナイズドセッション)

    成田 史生, 進藤 裕英

    M&M材料力学カンファレンス 2009 555-556 2009年7月24日

    出版者・発行元:一般社団法人日本機械学会

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    This paper discusses the delayed fracture and localized polarization switching near a crack tip in three-point bending piezoceramics under electromechanical loading. Delayed fracture experiments were performed on the piezoelectric ceramics with single-edge precracked-beam method. A nonlinear finite element analysis was also employed to calculate the fracture mechanics parameters such as energy release rate for the permeable, impermeable, open and discharging crack face boundary conditions. The effects of applied electric field and localized polarization switching on the fracture mechanics parameters and lifetime vs energy release rate curves were then examined

  42. 多層圧電薄膜アクチュエータの感知・応答機構解明とマルチスケール性能評価

    成田 史生, 進藤 裕英, 平間 充

    豊田研究報告 (62) 139-142 2009年5月

    出版者・発行元:豊田理化学研究所

    ISSN:0372-039X

  43. 121 CNT複合材料の極低温曲げ挙動に及ぼす界面損傷の影響(材料力学I)

    黒沼 遊, 進藤 裕英, 水戸 裕也, 竹田 智, 成田 史生

    講演論文集 2009 (44) 40-41 2009年3月13日

    出版者・発行元:一般社団法人日本機械学会

  44. 120 極低温における織物GFRP積層材料のモードIIIはく離疲労き裂進展挙動(材料力学I)

    三浦 正哉, 進藤 裕英, 成田 史生, 渡邉 慎也, 鈴木 雅人

    講演論文集 2009 (44) 38-39 2009年3月13日

    出版者・発行元:一般社団法人日本機械学会

  45. Mode 2 fatigue delamination growth behavior of woven GFRP laminates at cryogenic temperatures (JCOM-38 プログラム--材料・構造の複合化と機能化に関するシンポジウム)

    進藤 裕英, 竹田 智, 成田 史生

    JCOM講演論文集 38 91-94 2009年3月10日

    出版者・発行元:[日本材料学会]

  46. Analysis of mixed-mode interlaminar fracture and damage behavior of GFRP woven laminates at cryogenic temperatures

    Yasuhide Shindo, Fumio Narita, Susumu Takahashi, Takashi Sato, Tomo Takeda

    CRYOGENICS 49 (2) 80-83 2009年2月

    出版者・発行元:ELSEVIER SCI LTD

    DOI: 10.1016/j.cryogenics.2008.10.019  

    ISSN:0011-2275

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    The objective of this work is to investigate the interlaminar fracture and damage behavior of glass fiber reinforced polymer (GFRP) woven laminates loaded in a mixed-mode bending (MMB) apparatus at cryogenic temperatures. The finite element analysis (FEA) is used to determine the mixed-mode interlaminar fracture toughness of MMB specimen at room temperature (RT), liquid nitrogen temperature (77 K) and liquid helium temperature (4 K). A FEA coupled with damage is also employed to study the damage distributions within the MMB specimen and to examine the effect of damage on the mixed-mode energy release rate. The technique presented can be efficiently used for characterization of mixed-mode interlaminar fracture and damage behavior of woven laminate specimens at cryogenic temperatures. (C) 2008 Elsevier Ltd. All rights reserved.

  47. 極低温における織物ガラス繊維強化プラスチック積層材料のモードIII疲労はく離進展

    進藤 裕英, 成田 史生, 渡邉 慎也, 鈴木 雅人

    低温工学・超電導学会講演概要集 = Meetings of Cryogenics and Superconductivity 79 227-227 2008年11月12日

    ISSN:0919-5998

  48. 146 カーボンナノチューブ複合材料の極低温引張特性に関するマルチスケール評価(OS13.材料の組織・強度に関するマルチスケールアナリシス(4),オーガナイズドセッション)

    竹田 智, 進藤 裕英, 成田 史生, 水戸 裕也

    計算力学講演会講演論文集 2008 (21) 678-679 2008年11月1日

    出版者・発行元:一般社団法人日本機械学会

    ISSN:1348-026X

  49. 404 き裂を有するひし形介在物による弾性波散乱(材料力学1)

    進藤 裕英, 成田 史生

    日本機械学会東北支部秋季講演会講演論文集 2008 (44) 111-112 2008年9月27日

    出版者・発行元:一般社団法人日本機械学会

  50. OS0213 強磁場下におけるオーステナイト系ステンレス鋼の極低温弾塑性破壊特性評価(先端材料システムの力学とメゾスケールモデリング(2))

    鈴木 雅人, 進藤 裕英, 成田 史生

    M&M材料力学カンファレンス 2008 "OS0213-1"-"OS0213-2" 2008年9月16日

    出版者・発行元:一般社団法人日本機械学会

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    This paper studies the effect of magnetic field on the fracture behavior of the metastable austenitic stainless steels at cryogenic temperatures. Elastic-plastic fracture toughness tests were performed on compact tension (CT) specimens in liquid helium at 4 K with and without a magnetic field, and the effect of magnetic field on the cryogenic fracture toughness was discussed. Quantitative phase analysis was also done by magnetic method, and the fracture surfaces were examined by scanning electron microscopy (SEM) to correlate with the fracture properties.

  51. 強磁場下における準安定オーステナイト系ステンレス鋼の極低温破壊挙動

    進藤 裕英, 成田 史生, 鈴木 雅人

    低温工学・超電導学会講演概要集 = Meetings of Cryogenics and Superconductivity 78 42-42 2008年5月26日

    ISSN:0919-5998

  52. 傾斜機能圧電材料の感知・応答機構解明とマルチスケール性能評価

    成田 史生, 中川 淳, 進藤 裕英

    豊田研究報告 (61) 149-153 2008年5月

    出版者・発行元:豊田理化学研究所

    ISSN:0372-039X

  53. 142 星形介在物による平面弾性波散乱(材料力学II)

    仲村 祐, 進藤 裕英, 成田 史生

    講演論文集 2008 (43) 85-86 2008年3月15日

    出版者・発行元:一般社団法人日本機械学会

  54. 141 傾斜機能圧電トランスデューサの非線形動的曲げ・自己センシング(材料力学II)

    中川 淳, 進藤 裕英, 成田 史生

    講演論文集 2008 (43) 83-84 2008年3月15日

    出版者・発行元:一般社団法人日本機械学会

  55. 401 電場下における圧電セラミックスの三点曲げによる繰返し疲労き裂進展(OS4-1 先端材料システムの力学とメゾスケールモデリング,OS4 先端材料システムの力学とメゾスケールモデリング)

    成田 史生, 進藤 裕英

    M&M材料力学カンファレンス 2007 272-273 2007年10月24日

    出版者・発行元:一般社団法人日本機械学会

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    This paper investigates experimentally and analytically the cyclic fatigue crack growth in piezoelectric ceramics under electromechanical loading. Cyclic crack growth tests were conducted on PZT ceramics subjected to dc electric fields, and a finite element analysis was employed to calculate the maximum energy release rate for the permeable crack model. Based on bending experiments using single-edge precracked-beam specimens, cyclic fatigue crack growth rates are found to be sensitive to the maximum energy release rate and applied dc electric fields. Possible mechanisms for crack growth were discussed by scanning electron microscope (SEM) examination of the fracture surface of the PZT ceramics.

  56. 204 軟質磁性材料の破壊挙動に及ぼす磁場の影響(材料力学II,材料力学)

    進藤 裕英, 成田 史生

    日本機械学会東北支部秋季講演会講演論文集 2007 (43) 37-38 2007年9月29日

    出版者・発行元:一般社団法人日本機械学会

  57. 極低温における平織ガラス-エポキシ積層材料の4点曲げモードII層間破壊・損傷

    進藤 裕英, 佐藤 昂, 成田 史生, 渡邉 慎也, 真田 和昭

    低温工学・超電導学会講演概要集 = Meetings of Cryogenics and Superconductivity 76 193-193 2007年5月16日

    ISSN:0919-5998

  58. 4点曲げENF試験法による織物GFRP積層材料の極低温モード2層間破壊靭性評価

    進藤 裕英, 佐藤 昂, 成田 史生

    JCOM講演論文集 36 87-91 2007年3月8日

    出版者・発行元:[日本材料学会]

  59. 極低温における平織ガラス-エポキシ積層材料のモードII層間破壊・損傷

    佐藤 昂, 進藤 裕英, 成田 史生

    低温工学・超電導学会講演概要集 = Meetings of Cryogenics and Superconductivity 75 279-279 2006年11月15日

    ISSN:0919-5998

  60. 109 極低温における平織ガラス-エポキシ積層材料の引張・疲労挙動(材料力学II)

    進藤 裕英, 成田 史生, 佐藤 昂

    日本機械学会東北支部秋季講演会講演論文集 2006 (42) 17-18 2006年9月30日

    出版者・発行元:一般社団法人日本機械学会

  61. 極低温における織物GFRP積層材料のモードIII層間破壊靱性

    進藤 裕英, 堀口 勝三, 成田 史生, リゾフ ビクター

    低温工学・超電導学会講演概要集 = Meetings of Cryogenics and Superconductivity 74 248-248 2006年5月15日

    ISSN:0919-5998

  62. 508 円環状き裂を有する圧電繊維複合材料の電気弾性応答(材料力学I)

    林 森, 進藤 裕英, 成田 史生

    講演論文集 2006 (41) 207-208 2006年3月14日

    出版者・発行元:一般社団法人日本機械学会

  63. 514 極低温における平織ガラスーエポキシ積層材料のモードIはく離疲労き裂進展挙動(GS-9 破壊力学(1))

    進藤 裕英, 成田 史生, 堀口 勝三

    日本機械学会東北支部秋季講演会講演論文集 2005 (41) 203-204 2005年9月9日

    出版者・発行元:一般社団法人日本機械学会

  64. Mode I fatigue delamination growth in GFRP woven laminates at low temperatures

    SHINDO Yasuhide, INAMOTO Akihiro, NARITA Fumio, HORIGUCHI Katsumi

    低温工学・超電導学会講演概要集 = Meetings of Cryogenics and Superconductivity 72 191-191 2005年5月31日

    ISSN:0919-5998

  65. 201 中央駆動圧電トランスの電気破壊力学解析(材料力学 I,2.学術講演)

    林 森, 進藤 裕英, 成田 史生, 三上 賢

    講演論文集 2005 (40) 52-53 2005年3月15日

    出版者・発行元:一般社団法人日本機械学会

  66. 107 電極を有する圧電材料システムの電気弾性場集中と分域回転(セッション2)

    成田 史生, 進藤 裕英

    材料力学部門春のシンポジウム講演論文集 2005 17-20 2005年

    出版者・発行元:日本機械学会

  67. 202 極低温における織物ガラスーエポキシ積層材料の破壊靭性と損傷進展(セッション6)

    真田 和昭, 進藤 裕英, 成田 史生

    材料力学部門春のシンポジウム講演論文集 2005 63-66 2005年

    出版者・発行元:日本機械学会

  68. まとめ

    藤村 正哲, 進藤 裕英, 竹田 智, 成田 史生

    日本周産期・新生児医学会雑誌 = Journal of Japan Society of Perinatal and Neonatal Medicine 40 (4) 712-713 2004年12月1日

    出版者・発行元:一般社団法人日本機械学会

    ISSN:1348-964X

    詳細を見る 詳細を閉じる

    The purpose of this research is to characterize the cryogenic delamination growth behavior in woven glass fiber reinforced polymer (GFRP) composite laminates subjected to Mode II fatigue loading. Mode II fatigue delamination tests were performed at room temperature, liquid nitrogen temperature (77 K) and liquid helium temperature (4 K) using the four-point bend end-notched flexure (4ENF) test method, and the delamination growth rate data for the woven GFRP laminates were obtained. The energy release rate range was determined by the finite element method. Microscopic examinations of the specimen sections and fracture surfaces were also carried out The present results are discussed to obtain an understanding of the fatigue delamination growth mechanisms in the woven GFRP laminates under Mode II loading at cryogenic temperatures.

  69. Cryogenic Progressive Failure Behavior of Piain Weave Fabric-Reinforced Composites under Tensile Loading

    高野 哲, 進藤 裕英, 竹田 智, 成田 史生

    計算力学講演会講演論文集 2004 (17) 237-238 2004年11月17日

    出版者・発行元:一般社団法人日本機械学会

    ISSN:1348-026X

  70. Analysis of mode I Interlaminar Fracture and Damage Behavior of GFRP Woven Laminates at Cryogenic Temperatures

    進藤 裕英, 隅川 真由美, 竹田 智, 高野 哲, 成田 史生

    計算力学講演会講演論文集 2004 (17) 235-236 2004年11月17日

    出版者・発行元:一般社団法人日本機械学会

    ISSN:1348-026X

  71. Low-Temperature Cyclic Fatigue-Crack Growth Behavior in GFRP Woven Laminates

    進藤 裕英, 稲本 哲広, 成田 史生, 竹田 智, 熊谷 進

    低温工学・超電導学会講演概要集 = Meetings of Cryogenics and Superconductivity 71 246-246 2004年11月1日

    ISSN:0919-5998

  72. 磁場内における両側縁き裂を有する強磁性平板の引張試験と磁気弾性解析(材料力学II-1)

    進藤 裕英, 成田 史生, 堀口 勝三

    日本機械学会東北支部秋季講演会講演論文集 2004 (40) 41-42 2004年9月17日

    出版者・発行元:一般社団法人日本機械学会

  73. 223 面外せん断下における縁に平行なき裂を有する超磁歪帯板の磁気弾性解析(材料力学IV)

    成田 史生, 進藤 裕英, 豊田 諭史

    講演論文集 2004 (39) 90-91 2004年3月13日

    出版者・発行元:一般社団法人日本機械学会

  74. 222 極低温における織物GFRP積層材料の破壊靱性試験および損傷解析(材料力学IV)

    隅川 真由美, 進藤 裕英, 熊谷 進, 成田 史生, 堀口 勝三

    講演論文集 2004 (39) 88-89 2004年3月13日

    出版者・発行元:一般社団法人日本機械学会

  75. 213 PZT 系圧電セラミックスの改良型小型パンチ試験と電気破壊・分域回転特性

    進藤 裕英, 成田 史生, 堀口 勝三

    日本機械学会東北支部秋季講演会講演論文集 2003 (39) 59-60 2003年9月5日

    出版者・発行元:一般社団法人日本機械学会

  76. 515 界面に垂直なき裂を有する圧電積層材料におけるエネルギー解放率・エネルギー密度クライテリオンの比較

    林 森, 成田 史生, 進藤 裕英

    講演論文集 2003 (38) 210-211 2003年3月15日

    出版者・発行元:一般社団法人日本機械学会

  77. 514 き裂を有する二層平織ガラス繊維強化プラスチック積層材料の極低温応力拡大係数に及ぼす残留熱応力の影響

    竹田 智, 進藤 裕英, 成田 史生, 真田 和昭

    講演論文集 2003 (38) 208-209 2003年3月15日

    出版者・発行元:一般社団法人日本機械学会

  78. 513 き裂を有する極低温用平織 GFRP 積層板の熱弾性解析

    竹田 智, 進藤 裕英, 成田 史生, 熊谷 進

    講演論文集 2002 (37) 204-205 2002年3月16日

    出版者・発行元:一般社団法人日本機械学会

    詳細を見る 詳細を閉じる

    We deal with the thermal-mechanical response of multi-layered G-11 woven glass/epoxy laminates with cracks and temperature-dependent properties under tension at liquid helium temperature (4K). The composite material is assumed to be in generalized plane strain. Cracks are located in the fill fiber bundles and are assumed to span the width of the fill fiber bundles. Finite element model is used to study the influence of residual thermal stresses on the mechanical behavior of multi-layered woven laminates with cracks. Numerical calculations are carried out, and the Young's modulus and stress distributions near the crack tip are shown graphically.

  79. 圧電応用デバイス信頼性・耐久性評価のための電気破壊力学的研究

    成田 史生, 堀口 勝三, 進藤 裕英

    シンポジウム電磁力関連のダイナミックス講演論文集 13 16-19 2001年6月20日

  80. 503 予き裂導入破壊試験法による圧電セラミックスの電気破壊特性評価(材料物性)

    村上 平八郎, 進藤 裕英, 堀口 勝三, 成田 史生

    講演論文集 2000 (35) 162-163 2000年3月11日

    出版者・発行元:一般社団法人日本機械学会

  81. 面外圧電理論による円形介在物の動的解析

    森林 宏和, 進藤 裕英, 成田 史生

    シンポジウム電磁力関連のダイナミックス講演論文集 11 322-325 1999年10月13日

  82. Anti-Plane Shear Crack in a Piezoelectric Layer Bonded to Dissimilar Half Spaces

    Narita Fumio, Shindo Yasuhide, Watanabe Koji

    JSME international journal. Series A, Solid mechanics and material engineering 42 (1) 66-72 1999年1月15日

    出版者・発行元:日本機械学会

    ISSN:1344-7912

    詳細を見る 詳細を閉じる

    Following the theory of linear piezoelectricity, we consider the electroelastic problem for a piezoelectric layer with a crack bonded to two elastic half planes under antiplane shear loading. The crack parallel to the interfaces is in the mid-plane of the piezoelectric layer. Fourier transforms are used to reduce the problem to the solution of a pair of dual integral equations. The solution of the dual integral equations is then expressed in terms of a Fredholm integral equation of the second kind. Numerical values of the stress intensity factor for some piezoelectric laminates are obtained, and the results are plotted to display the electroelastic interactions.

  83. 縦せん断下における界面に平行なき裂を有する圧電積層材料の電気弾性解析

    進藤 裕英, 成田 史生, 渡辺 浩司

    シンポジウム電磁力関連のダイナミックス講演論文集 10 97-102 1998年10月23日

  84. Scattering of Love Waves by a Surface-Breaking Crack in Piezoelectric Layered Media

    Narita Fumio, Shindo Yasuhide

    JSME international journal. Series A, Solid mechanics and material engineering 41 (1) 40-48 1998年1月15日

    出版者・発行元:日本機械学会

    ISSN:1344-7912

    詳細を見る 詳細を閉じる

    Based on the dynamic theory of linear piezoelectricity, we investigate the scattering of Love waves by a surface-breaking crack in a layered piezoelectric solid. The piezoelectric layer is perfectly bonded to a half-space of a different elastic solid and the crack is normal to the free surface. Both cases of a partially broken layer and a completely broken layer are studied. By the use of Fourier transform techniques, the mixed boundary value problem is reduced to a singular integral equation. The singular integral equation is solved numerically to determine the dynamic stress intensity factor and the dynamic energy release rate as a function of a dimensionless frequency for various ratios of crack depth to layer thickness, and the results are presented in graphical form.

︎全件表示 ︎最初の5件までを表示

書籍等出版物 6

  1. 楽しく学ぶ破壊力学

    成田史生, 大宮正毅, 荒木稚子

    朝倉書店 2020年4月

  2. 楽しく学ぶ材料力学

    成田史生, 森本卓也, 村澤剛

    朝倉書店 2017年4月

  3. Woven Composites, Computational and Experimental Methods in Structures - Vol. 6, M.H.Aliabadi (Ed.)

    Y. Shindo, T. Takeda, F. Narita

    Imperial College Press/World Scientific 2015年

  4. Handbook on Micromechanics and Nanomechanics, S. Li and X.-L. Gao (Eds.)

    Yasuhide Shindo, Fumio Narita

    Pan Stanford Publishing Pte. Ltd. 2013年

  5. Smart Actuation and Sensing Systems - Recent Advances and Future Challenges, Rocco Vertechy and Gabriele Vassura (Eds.)

    Yasuhide Shindo, Fumio Narita

    InTech Publishing Company 2012年9月

  6. Composite Materials Research Progress, Lucas P. Durand (Ed.)

    Yasuhide Shindo, Fumio Narita

    Nova Science Publishers, Inc. 2008年

︎全件表示 ︎最初の5件までを表示

講演・口頭発表等 25

  1. Effect of Magnetic Fields on the Fatigue Behavior of Cracked Magnetostrictive Materials in Three-Point Bending 国際会議

    International Conference on Mechanics of Complex Solids and Fluids 2015年5月17日

  2. Three-Dimensional Cryomechanics Analysis of Satin Woven Carbon/Polymer Composites with Cracks 国際会議

    23rd International Congress of Theoretical and Applied Mechanics 2012年8月20日

  3. Electromechanical Filed Concentrations and Polarization Switching Due to Interdigitated Electrodes in Piezoelectric Macro-Fiber Composites under Tension 国際会議

    SPIE 18th Annual International Symposium on Smart Structures/NDE 2011年3月6日

  4. Nonlinear Bending Response of Terfenol-D/PZT Laminated Devices under Electromagnetic Fields 国際会議

    SPIE 17th Annual International Symposium on Smart Structures/NDE 2010年3月7日

  5. Effect of Magnetic Field on the Bending Response of Magnetostrictive/Piezoelectric Laminated Actuators 国際会議

    SPIE 16th Annual International Symposium on Smart Structures/NDE 2009年3月8日

  6. 傾斜機能圧電センサ・アクチュエータの感知・応答特性

    中川 淳, 成田史生, 進藤裕英, 水戸裕也

    第19回「電磁力関連のダイナミクス」シンポジウム 2007年5月16日

  7. Fatigue of Cracked PZT Ceramics in Three-Point Bending under Electric Fields 国際会議

    F. Narita, Y. Shindo, F. Saito

    SPIE’s International Symposium on Smart Structures and Materials, Active Materials: Behavior and Mechanics 2007年3月18日

  8. Electroelastic Field Concentrations and Frequency Properties of Rosen-Type Piezoelectric Transformers 国際会議

    Smart Structures and Materials and NDE for Health Monitoring and Diagnostics, SPIE Event 2006年2月26日

  9. Nonlinear Bending Behavior of Functionally Graded Piezoelectric Actuators under Electric Fields

    成田史生, 進藤裕英, 三上 賢, 斉藤文利

    日本機械学会2005年度年次大会 2005年9月19日

  10. 極低温における平織ガラス-エポキシ積層材料のモードIはく離疲労き裂進展挙動

    進藤裕英, 成田史生, 堀口勝三

    日本機械学会東北支部第41期秋期講演会 2005年9月9日

  11. ローゼン型圧電トランスの電気弾性場集中と振動数特性

    成田史生, 進藤裕英, 三上賢

    第17回「電磁力関連のダイナミクス」シンポジウム 2005年6月22日

  12. 電極を有する圧電材料システムの電気弾性場集中と分域回転

    成田史生, 進藤裕英

    日本機械学会M&M信州スプリングシンポジウム 2005年3月14日

  13. 交流電場下における圧電積層アクチュエータの曲げと分域壁移動

    成田史生, 進藤裕英, 三上 賢

    第54回理論応用力学講演会 2005年1月25日

  14. Analysis of Mode I Interlaminar Fracture and Damage Behavior of GFRP Woven Laminates at Cryogenic Temperatures

    進藤裕英, 隅川真由美, 竹田智, 高野哲, 成田史生

    日本機械学会第17回計算力学講演会 2004年11月18日

  15. Electroelastic Fields Concentrations and Polarization Switching by Circular Electrodes in Piezoelectric Disk Composites 国際会議

    F. Narita, Y. Shindo, M. Karaiwa

    21st International Congress of Theoretical and Applied Mechanics 2004年8月15日

  16. Analysis of Tensile Testing of a Soft Ferromagnetic Elastic Strip Containing a Central Crack under a Magnetic Field 国際会議

    D. Sekiya, Y. Shindo, F. Narita, K. Horiguchi

    21st International Congress of Theoretical and Applied Mechanics 2004年8月15日

  17. 圧電トランスの電気破壊力学解析と分域回転

    唐岩賢, 成田史生, 進藤裕英

    日本機械学会M&M2004材料力学カンファレンス 2004年7月21日

  18. 電極を有する積層圧電アクチュエータの電気弾性場集中と分域回転

    進藤裕英, 成田史生, 堀口勝三

    日本機械学会第16回計算力学講演会 2003年11月22日

  19. Electroelastic Bending and Polarization Switching of Piezoelectric Laminated Actuators 国際会議

    F. Narita, Y. Shindo, K. Hayashi, M. Yoshida

    Second MIT Conference on Computational Fluid and Solid Mechanics 2003年6月17日

  20. 円形電極を有する圧電円板の電気弾性場集中と分域回転

    成田史生, 吉田宗之, 進藤裕英, 唐岩 賢, 堀口勝三

    第15回「電磁力関連のダイナミックス」シンポジウム 2003年5月28日

  21. 円板状き裂を有する圧電セラミックス円柱の衝撃応答

    林 森, 成田史生, 進藤裕英

    第52回理論応用力学講演会 2003年1月28日

  22. 圧電セラミックスの電気弾性破壊力学

    成田史生, 進藤裕英, 堀口勝三

    日本機械学会M&Mレイクサイドサマーシンポジウム 2002年8月7日

  23. Electroelastic Fracture Mechanics of Piezoelectric Ceramics 国際会議

    F. Narita, Y. Shindo, K. Horiguchi

    14th US National Congress of Theoretical and Applied Mechanics, Symposium on Electro-Magneto-Mechanics 2002年6月23日

  24. 圧電セラミックスの破壊・分域回転特性評価

    真柄安代, 吉田宗之, 進藤裕英, 成田史生, 堀口勝三

    第14回「電磁力関連のダイナミックス」シンポジウム 2002年5月22日

  25. 圧電応用デバイス信頼性・耐久性評価のための電気破壊力学

    成田史生, 堀口勝三, 進藤裕英

    第13回「電磁力関連のダイナミックス」シンポジウム 2001年6月21日

︎全件表示 ︎最初の5件までを表示

産業財産権 6

  1. 振動発電装置

    小野寺隆一, 田山巌, 佐藤武信, 江幡貴司, 成田史生

    特許第6991685号

    産業財産権の種類: 特許権

  2. 複合強化型の磁歪複合材料及びその製造方法

    成田史生, 古屋泰文, 表研次

    特許6884299号

    産業財産権の種類: 特許権

  3. 振動発電装置およびアクチュエータ

    成田史生, 小野寺隆一, 田山巌, 千葉大喜, 佐々達郎, 佐藤武信, 江幡貴司

    特許第6653834号

    産業財産権の種類: 特許権

  4. ナノセルロースを含む複合糸の製造方法、ナノセルロースを含む複合糸および蚕用の餌

    呉宸, 栗田大樹, 王真金, 成田史生

    産業財産権の種類: 特許権

  5. 発電装置、施設の環境情報センシングシステムおよび人/動物センシングシステム

    成田史生, 槙原幹十朗, 橋本善一, 菊田純一, 阿部晋一

    産業財産権の種類: 特許権

  6. エネルギー変換部材、振動発電装置、力センサー装置およびアクチュエータ

    成田史生, 小野寺隆一, 田山巌, 千葉大喜, 佐々達郎, 佐藤武信, 江幡貴司

    産業財産権の種類: 特許権

︎全件表示 ︎最初の5件までを表示

共同研究・競争的資金等の研究課題 22

  1. 機能傾斜・最適化による新規圧電・磁歪複合材料の創成とエネルギー変換現象の解明

    成田 史生, 川上 祥広, 荒木 稚子, 栗田 大樹, 森 孝太郎, 宮本 直人

    2022年4月1日 ~ 2026年3月31日

  2. IoT社会を実現するマルチ環境発電材料・デバイス国際研究拠点形成

    2020年4月 ~ 2025年3月

  3. 磁歪繊維複合材料を用いた多機能ネジ型デバイスの開発

    森 孝太郎, 成田 史生

    2021年4月1日 ~ 2024年3月31日

    詳細を見る 詳細を閉じる

    本研究は,軽量,高強度かつ力に対する感知機能を有し磁歪複合材料製のネジの開発を目的に,磁歪複合材料製ネジの感知・締結特性を理論的・実験的に解明するものである.また,感知・締結特性だけでなく,振動・衝撃による発電特性についても検討し,大量に配置することを前提とした,多機能なネジ型デバイスの設計理論・技術の確立も目指すものである.そこで,本年度は,FeCo長繊維を芯とした磁歪材料/エポキシ樹脂製ネジの作製および締結試験および理論計算を行い,感知特性の調査を行った. 上記研究に関して,まず,FeCo長繊維を芯とした磁歪材料/エポキシ樹脂製ネジを作製した.ここで,FeCo長繊維に予荷重およびバイアス磁場を与えた状態で樹脂を硬化させることにより,ネジ内部に残留応力を発生させ,磁束密度変化量を向上させた.次に,締結試験を行い,軸方向ひずみおよびネジ先端の磁束密度変化を計測し,締付けトルクと軸力および磁束密度変化の関係を評価した.また,磁歪複合材料製ネジにバイアス磁場を印加した状態での締結試験も行い,バイアス磁場と磁束密度変化の関係についても調べ,試験時のバイアス磁場が及ぼす影響についても調査した.また,上記実験に理論計算結果を加え,作製した磁歪複合材料製ネジの機械的特性および締結特性についても評価した. 本年度は以上の通り研究を実施した.今後も短繊維や粉末状の磁歪材料を用いた磁歪複合材料製ネジを作製・試験を行い,引き続き磁歪複合材料製のネジの電磁力学特性の解明およびネジ型デバイスの多機能化や応用可能性について検討していく.

  4. 圧電・磁歪材料力学設計による電子複合材料の高エネルギー変換機能の創出

    成田 史生, 川上 祥広, 荒木 稚子, 栗田 大樹, 森 孝太郎, 宮本 直人

    提供機関:Japan Society for the Promotion of Science

    制度名:Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (A)

    研究種目:Grant-in-Aid for Scientific Research (A)

    研究機関:Tohoku University

    2019年4月1日 ~ 2023年3月31日

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    本研究は,温度変化・履歴や振動・衝撃を電気に変換する機能性複合材料を開発し,電磁エネルギー変換機能を解明するものである.得られた成果を要約すると以下の通りである. 1.(a) 圧電繊維/アルミニウム(Al)複合材料の電気力学応答に及ぼす残留熱応力の影響を有限要素法により解明した.(b) 圧電繊維/エポキシ複合材料の動的電気力学応答を有限要素解析し,ウイルスレベルの質量変化による出力電圧を明らかにした. 2.(a) 圧電ナノ粒子分散樹脂を作製し,炭素繊維強化プラスチック(CFRP)を積層して電極として用い,コロナ放電分極に成功した.そして,曲げ振動や衝撃荷重から電圧・電力を回収できるCFRP複合材料の実現可能性を示した.(b) 強靱な繊維と加工が容易な熱可塑性樹脂との複合化に着目し,圧電ナノ粒子分散ムライト繊維織物複合材料を作製して,振動・衝撃発電性能を解明した.(c) 圧電ナノ粒子/ポリフッ化ビニリデン三フッ化エチレン傾斜機能材料の開発に成功した. 3.(a) 鉄コバルト(Fe-Co)短繊維・粒子とエポキシ・アクリル・ポリウレタン樹脂やナノセルロースからなる複合材料およびFe-Co長繊維分散ガラス・炭素繊維強化複合材料を作製し,磁場-力学場相互干渉を解明した.(b) Fe-Co繊維をAlに埋め込む技術を確立し,衝撃を電気に変換する軽金属複合材料を開発した他,2本のFe-Co繊維を撚って埋め込み,高出力化に成功した. 4.(a) Fe-Coの磁気・磁歪挙動に及ぼす微量添加元素や磁場中熱処理の影響を解明した.(b)アモルファス磁歪薄膜をSi基板上に成膜し,残留応力と透磁率の関係を評価した.(c) 空気中ウイルスの検出を目指し,Fe-Co/ニッケル積層材料を作製して,動的磁気力学応答を解明した.また,Fe-Coをコバルト鉄酸化物(CoFeO)基板に成膜する手法について検討中である.

  5. 生分解性シルクタンパク足場材料の創成と3D印刷による細胞培養用プレートへの応用

    成田 史生, 栗田 大樹

    提供機関:Japan Society for the Promotion of Science

    制度名:Grants-in-Aid for Scientific Research

    研究種目:Grant-in-Aid for Challenging Research (Pioneering)

    研究機関:Tohoku University

    2019年6月28日 ~ 2022年3月31日

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    本研究では,はじめに,シルクファイバーにセルロースナノファイバーを分散し,引張特性を評価して,特性向上メカニズムについて明らかにした.次に,シルクフィブロインの濃度を変えたPEGDMA/シルクフィブロインハイドロゲルの光造形に成功した.開発されたハイドロゲルは,幅広い圧縮弾性率を示し,筋肉組織,脂肪,骨などの様々な幹細胞の代替となり得ることが示唆された

  6. 圧電・磁歪効果を利用した機能性炭素繊維強化プラスチックの開発と飛行振動発電技術の創出

    2019年10月 ~ 2020年9月

  7. 環境発電IoTデバイス適用への磁歪・圧電界面ドメイン増殖型高感度スマート複合材料

    古屋 泰文, 千葉 晶彦, 成田 史生, 和田 智志, 中尾 航, 戸津 健太郎, 丹波 澄雄

    提供機関:Japan Society for the Promotion of Science

    制度名:Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)

    研究種目:Grant-in-Aid for Scientific Research (B)

    研究機関:Tohoku University

    2017年4月1日 ~ 2020年3月31日

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    本研究では,自立分散型IoTセンサや環境発電エネルギーハーベスト型の高性能スマート材料・デバイス設計・開発を行うが、その特徴は、大きなバイアス応力・逆磁歪漏れ磁束効果を活かせる、圧電体で表面を被覆した磁歪材(薄板、ファイバ)埋込み型の複合機能型材料の創生を目指す。 <BR> その目標達成ために、初年度(H.29)には、まず、磁歪および圧電要素材料の物性評価を実施した。特に、磁歪合金の加工度合と熱処理条件を変えて微視的な組織改質を実施して、一層の磁歪量および磁歪感受率の3倍以上の増大を達成できた。また、磁区の増殖度合いを非破壊的に評価可能な、磁化過程での磁区発生・移動を反映する、ミクロ磁気的雑音(バルクハウゼンノイズ,BHN)計測システムを構築して、異相界面部でのドメイン(磁区,分極域)増殖とその動的挙動(ドメインダイナミクス)へのシナジー効果を診断できるであろう基本計測技術を構築した。これらにより、高感度化させたFeCo過剰型組成(FeCo原子%)磁歪合金ワイヤーを用いた応力センサの可能性を実証できた。他方、圧電体では、PZT粉を入手して、その物性値およびポリマー系部材に分散凝固させた、磁歪被覆材を試作した。 <BR> これらにより、圧電体で表面を被覆した磁歪材(薄板、ファイバ)埋込み型の複合機能型材料の試作する準備ができた。なお、磁歪合金(FeCo過剰型)の改質による高感度化および磁気的雑音(バルクハウゼンノイズ,BHN)計測システム)の応力依存性については、学会発表および2編の論文投稿(和文および英文誌)を行って、成果の公表に努めた。

  8. 超高圧縮応力を内包した金属基圧電複合材料の機能発現メカニズム解明

    浅沼 博, 成田 史生, 佐藤 宏司, 柳迫 徹郎

    提供機関:Japan Society for the Promotion of Science

    制度名:Grants-in-Aid for Scientific Research

    研究種目:Grant-in-Aid for Scientific Research (B)

    研究機関:Chiba University

    2017年4月1日 ~ 2020年3月31日

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    金属コア圧電ファイバ/アルミニウム複合材料(Piezo-Al)は,複合化時に生じる極めて高い残留圧縮応力下でも圧電性を発現する他に類の無い圧電複合材料であるが,この圧縮応力下での機能発現に関して不明な点が多い.当該年度では,そのメカニズム解明のため,下記の項目を実施,検討した. 1)Piezo-Al中の圧電ファイバは複合化時に圧縮熱残留応力が負荷される.この圧縮応力が圧電ファイバの分極にどのような影響を与えているかを検討するため,分極状態の評価を検討した.Piezo-Alは円筒型コンデンサ形状をしており,従来の圧電材料分極評価手法では正確な評価ができない.そのため,ペレット状の材料物性値を圧縮応力下で計測できるシステムを構築し,物性値の評価が可能となった.加えて,FEM解析において,複合化プロセス時に生じる残留応力の算出を行い,約1GPaという極めて高い圧縮応力が圧電ファイバ-マトリックス界面近傍に生じることが確認された.この結果は先行研究による実測値とよく一致していることから,良い精度で実験を再現できており,解析による評価の目途が立った. 2)複合化された圧電ファイバは圧縮応力により破断強度が向上する可能性が示唆されている.この圧縮応力による機械的特性向上を評価するため複雑な構造を持つPiezo-Alではなく,単純構造を持つ圧電セラミックス/アルミニウム複合材料を作製し,3点曲げ試験により圧電セラミックスの強度を確認し,ワイブル解析による統計的な処理を行った.この結果,複合化により形状母数は4.3から10.9へ,尺度母数は106MPaから161MPaへそれぞれ向上しており,定量的に圧縮応力が機械的特性に及ぼす影響が確認できた.しかしながら,評価した試験片が10個程度と統計的には少ない試料数であったため,試行回数を増加させ,ワイブル解析の精度を向上させる必要がある.

  9. 特殊温度発電を実現する圧電ナノ粒子分散ポリマー複合材料の開発と電気力学的挙動評価

    成田 史生, 栗田 大樹, 熊谷 進, 森 孝太郎

    提供機関:Japan Society for the Promotion of Science

    制度名:Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)

    研究種目:Grant-in-Aid for Scientific Research (B)

    研究機関:Tohoku University

    2016年4月1日 ~ 2019年3月31日

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    本研究では,非鉛系の圧電複合材料を取り上げ,温度発電・圧電応答挙動を数値シミュレーション・実験両面から解明した.具体的には,圧電/Cuユニモルフ,圧電ナノ粒子分散ポリマーフィルム等を試作し,温度変化による出力電圧計測や圧電応答機能評価を行った.また,マルチフィジックス数値シミュレーションを実施して,実験結果に理論的検討を加えた.さらに,圧電複合材料の材料・構造最適化について考察した.

  10. 逆磁歪効果を利用した衝撃発電ヒール・パンプスの開発 ~スポーツシューズへの展開を目指して~

    2017年10月 ~ 2018年9月

  11. 生体用鉄ガリウム系磁歪材料システムの電磁メゾ力学特性解明と高性能・省電力化

    進藤 裕英, 成田 史生, 竹田 智

    提供機関:Japan Society for the Promotion of Science

    制度名:Grants-in-Aid for Scientific Research Grant-in-Aid for Challenging Exploratory Research

    研究種目:Grant-in-Aid for Challenging Exploratory Research

    研究機関:Tohoku University

    2014年4月1日 ~ 2015年3月31日

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    本研究は,生体用自己給電電磁デバイスの設計法及び信頼性・耐久性評価法を開発することを目的に,先端超磁歪材料システムを取り上げ,微視構造および磁壁移動・磁区回転等の影響を考慮して,環境発電特性および破壊・疲労特性に及ぼす磁場の影響をマルチフィジックス数値シミュレーション・実験両面から解明したものである.また,得られたデータを蓄積し,出力電力が大きく長寿命な磁歪材料システムの材料・構造について検討を加えている.

  12. スマート圧電材料・薄膜システムのメゾ力学設計・開発と高効率・環境負荷低減化

    進藤 裕英, 成田 史生, 竹田 智

    提供機関:Japan Society for the Promotion of Science

    制度名:Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)

    研究種目:Grant-in-Aid for Scientific Research (B)

    研究機関:Tohoku University

    2012年4月1日 ~ 2015年3月31日

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    本研究は,次世代環境配慮型スマートデバイスのメゾ力学設計指針・開発思想を提供することを目的に,圧電材料・薄膜システムの検知・応答機能及び破壊・疲労挙動をマルチフィジックス数値シミュレーション(電場・力学場相互干渉,マイクロ・ナノ構造,化学組成・添加元素,焼成・蒸着の時間・温度等を考慮)・実験両面から解明したものである.また,得られた結果を総合的に検討し,スマート圧電材料・薄膜システムのメゾ強度・機能評価を行って,学問体系の確立と応用に寄与している.

  13. 2次電池を有するチタバリ系電子複合材料の性能評価とワイドバンドギャップ化

    成田 史生

    提供機関:Japan Society for the Promotion of Science

    制度名:Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C)

    研究種目:Grant-in-Aid for Scientific Research (C)

    研究機関:Tohoku University

    2012年4月1日 ~ 2015年3月31日

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    本研究は,次世代環境配慮型スマート電子複合材料のメゾ力学設計指針を提供することを目的に,チタバリ系電子複合材料の検知・応答機能及び発電特性をマルチフィジックス数値シミュレーション(電場・力学場相互干渉,マイクロ・ナノ構造,化学組成・添加元素,焼成・蒸着の時間・温度等を考慮)・実験両面から解明したものである.また,得られた電子複合材料の検知・応答機能及び発電特性を総合的に検討し,性能を解明・制御して,最適な材料・構造を見出している.

  14. 知的電子複合材料の感知・応答・記憶及び破壊・損傷特性制御による高性能・長寿命化

    成田 史生, 進藤 裕英

    提供機関:Japan Society for the Promotion of Science

    制度名:Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C)

    研究種目:Grant-in-Aid for Scientific Research (C)

    研究機関:Tohoku University

    2008年 ~ 2010年

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    本研究は, 知的電子複合材料の設計法及び強度・機能評価法を開発することを目的に, 圧電効果を有する電子複合材料の感知・応答・記憶及び破壊・損傷特性評価を行ったものである.具体的には, 傾斜機能圧電材料, 圧電繊維/エポキシ複合材料, 圧電積層材料の電気力学的挙動を理論・実験両面から解明し, 高性能・長寿命複合材料設計に資する有益な結果を得た.

  15. 先端圧電材料・薄膜システムのデバイスメゾ設計と強度・機能評価

    進藤 裕英, 成田 史生

    提供機関:Japan Society for the Promotion of Science

    制度名:Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)

    研究種目:Grant-in-Aid for Scientific Research (B)

    研究機関:Tohoku University

    2006年 ~ 2009年

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    本研究は,次世代知的電子システム,高性能マイクロ・ナノデバイス等の設計法及び信頼性・耐久性評価法を開発することを目的に,先端圧電材料・薄膜システムの電気力学特性及び破壊・疲労特性等に及ぼす電場及び分域壁移動・分極回転の影響を理論・実験両面から解明したものである.

  16. 超磁歪材料・薄膜システムの内部微視構造変化を考慮した電磁破壊・メゾ力学

    進藤 裕英, 成田 史生, 堀口 勝三

    2005年 ~ 2007年

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    本研究は,知的・電子材料システムの設計・開発及び信頼性・耐久性評価に資することを目的に,先端超磁歪材料・薄膜システムの電磁破壊力学特性を,マイクロ・ナノ構造及び磁区等との相互作用を考慮して解明したものである.得られた成果を要約すると以下の通りである. 1.磁歪材料Terfeno1-D(Tb_<0.3>Dy_<0.7>Fe_<1.9>)層と金属(SUS316・Cu・Al)基板から構成される超磁歪積層アクチュエータを作製した.そして,アクチュエータに磁場を印加し,伸びひずみを計測して,磁歪特性を評価した.また,有限要素解析(圧磁係数に及ぼす磁場の影響考慮)により,実験結果に理論的検討を加え,磁区回転に起因する非線形磁気力学特性解明に成功した.さらに,基板の先端たわみ及び内部応力に及ぼす磁場の影響を明らかにした. 2. (1)超磁歪/圧電積層デバイスの電磁力学特性に及ぼす内部微視構造変化(磁壁移動・分域壁移動等)の影響解明を目指し,傾斜機能圧電センサ・アクチュエータの動的曲げ試験・非線形有限要素解析を行った.そして,感知・応答特性に及ぼす電場・周波数及び分域壁移動等の影響を解明した. (2)Terfenol-D層と圧電(PZT)板から構成される超磁歪/圧電積層デバイスを作製し,磁場による伸びひずみを計測して,磁歪特性を明らかにした.また,非線形有限要素解析(圧磁係数に及ぼす磁場の影響考慮)を行い,圧電板の先端たわみ・伸び,出力電圧及び内部応力に及ぼす磁場及び超磁歪層厚・積層構造の影響について検討を加えた.

  17. 電子複合材料の構造・界面制御と知能デバイス化に関する研究

    成田 史生

    2005年 ~ 2007年

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    本研究は,センサ・アクチュエータ等を一体融合化した知能電子デバイスの設計・開発に資することを目的に,圧電効果を有する電子複合材料の感知・応答特性評価を数値シミュレーション・実験両面から行ったものである.得られた成果を要約すると以下の通りである. 1.(1)交流電場下における両端固定傾斜機能圧電アクチュエータの非線形動的曲げ挙動を理論・実験両面から明らかにした.有限要素解析は,圧電層の分域壁移動を考慮して行い,たわみ・音圧及び内部応力に及ぼす交流電圧・傾斜組成分布の影響を解明した.また,音圧を測定し,解析結果と実験結果を比較・検討して,解析モデルの妥当性を検証した. (2)交流電場下における両端固定傾斜機能圧電トランスデューサを対象に,非線形動的曲げ・出力電圧挙動に関する有限要素解析(分域壁移動を考慮)・試験を行い,音圧・出力電圧及び内部電場・応力に及ぼす交流電圧・傾斜組成分布の影響を解明した. (3)片持ち傾斜機能圧電トランスデューサを対象に,交流電場・集中荷重による先端たわみ・出力電圧及び内部応力を有限要素解析(分域壁移動を考慮)し,非線形動的曲げ・出力電圧挙動を解明した.また,先端たわみ・出力電圧を測定し,解析結果と比較・考察した. 2.(1)円環状き裂を有する圧電繊維複合材料の軸対称問題を取り上げ,き裂の電気弾性挙動を理論的に解明した. (2)1-3圧電コンポジットの電気力学場集中及び周波数特性に関する数値シミュレーション・実験を行い,静的・動的電場誘起の変位・内部応力に及ぼす角柱・円柱状圧電ロッド体積含有率の影響を解明した.

  18. 小型切欠き曲げ試験による超電導応用機器材料システムの極低温破壊強度特性評価

    堀口 勝三, 進藤 裕英, 成田 史生, 田村 仁

    提供機関:Japan Society for the Promotion of Science

    制度名:Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C)

    研究種目:Grant-in-Aid for Scientific Research (C)

    2005年 ~ 2006年

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    本研究は、小型切欠き曲げ試験片を用いた構造・絶縁・超電導材料の極低温破壊強度特性簡便評価法の開発・応用を行ったものである。すなわち、超電導応用機器の設計・開発及び信頼性・安全性評価に資することを目的に、2年間の研究を実施し、以下の成果を得た。 1.準安定オーステナイト系ステンレス鋼SUS304の極低温(液体ヘリウム温度4K)・強磁場(6T ; T : tesla)下における引張・弾塑性破壊靱性試験を行い、極低温引張・破壊特性に及ぼす磁場誘起マルテンサイト変態の影響を明らかにした。 2.オーステナイト系ステンレス鋼溶接材の溶接熱影響部に切欠きを導入した試験片を用いて極低温切欠き曲げ試験を行い、極低温破壊強度特性に及ぼす組織・介在物、ひずみ誘起マルテンサイト変態等の影響を明らかにした。また、溶接部の極低温硬さを計測し、破壊強度特性との関連を明らかにした。 3.織物GFRP(ガラス繊維強化プラスチック)積層材料を対象に、AE(アコースティックエミッション)法を併用して室温・77K・20K・4Kにおける引張試験を行い、各温度における引張・損傷挙動を解明した。また、損傷進展解析(有限要素法)を行い、損傷発生・進展挙動、試験片縁の応力分布を明らかにして、実験結果に理論的検討を加えた。 4.ガラス繊維表面に処理を施した織物GFRP積層材料を対象に、繊維・樹脂間の極低温界面特性を評価し、界面特性に及ぼす繊維表面処理条件の影響を明らかにした。また、繊維表面処理を施した織物GFRP積層材料の極低温引張・切欠き曲げ試験、試験片表面・破面観察及び数値シミュレーションを行い、極低温損傷・破壊強度特性に及ぼす繊維・樹脂界面特性の影響を解明・考察した。 5.希土類バルク超電導体として応用が期待されているNd(ネオジウム)・Sm(サマリウム)・Gd(ガドリニウム)系を提試材として極低温切欠き曲げ試験を行い、き裂進展特性に及ぼす不純物・欠陥等の影響を明らかにし、破壊強度改善に向けて検討した。また、接合部の極低温・強磁場破壊強度特性も評価し、最適接合条件についても検討を加えた。

  19. 先端圧電材料システムの電気破壊・疲労特性解明

    進藤 裕英, 堀口 勝三, 成田 史生

    提供機関:Japan Society for the Promotion of Science

    制度名:Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)

    研究種目:Grant-in-Aid for Scientific Research (B)

    研究機関:TOHOKU UNIVERSITY

    2002年 ~ 2005年

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    本研究は,先端圧電材料システムの破壊・疲労特性に及ぼす電気弾性・非弾性相互干渉の影響解明に関する理論的・実験的研究を行ったものである.すなわち,知的・電子材料システムの設計・開発及び寿命・構造健全性評価に資することを目的に,4年間の研究を実施し,以下の成果を得た. 1.き裂を有する圧電材料システムの電気弾性解析を行い,エネルギー解放率・エネルギー密度等に及ぼす電場の影響を解明し,衝撃応答や疲労き裂成長挙動についても同様に検討・考察を加えた.また,き裂近傍における局所分域回転を考慮した有限要素解析法を開発し,圧電材料システムの非線形破壊力学的挙動解明に成功した. 2.圧電セラミックスの圧子圧入・予き裂導入破壊・ダブルトーション試験及び有限要素解析を行い,破壊・変形特性に及ぼす電場・分域回転の影響を解明した.また,圧電セラミックスを対象に,改良型小型パンチ(MSP)試験・有限要素解析を行い,破壊時の荷重及びMSPエネルギーに及ぼす電場・分域回転の影響を明らかにした. 3.片側縁き裂を有する圧電セラミックスの三点曲げによる静疲労試験及び繰返し疲労き裂進展試験を行い,破断時間や疲労き裂進展挙動に及ぼす電場の影響を解明した.また,走査型電子顕微鏡による破面観察を行い,粒内・粒界破壊について考察した.さらに,有限要素解析を行い,エネルギー解放率を求めて,実験結果に理論的検討を加えた. 4.表面・内部電極を有する圧電積層材料の電極端近傍応力・電束密度集中について検討・考察した.また,表面・内部電極を有する圧電円柱や圧電積層アクチュエータの電極端近傍における電気弾性場集中に及ぼす印加電圧・分域回転の影響及び非線形挙動を理論的・実験的に解明した.さらに,三層・傾斜機能圧電アクチュエータの非線形曲げ試験・有限要素解析を行い,たわみに及ぼす直流・交流電場及び分域回転・分域壁移動の影響を明らかにした.

  20. 先端圧電材料システムの分域回転・結晶粒再配向を考慮した電気破壊・メゾ力学

    進藤 裕英, 成田 史生, 堀口 勝三

    2001年 ~ 2003年

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    本研究は,先端圧電材料システムの電気破壊力学特性を,マイクロ構造及び分域・分極ならびに欠陥(き裂等)との相互作用を考慮して解明したものである.すなわち,知的・電子材料システム,マイクロシステム等の信頼性・耐久性評価に資することを目的に,電気破壊・メゾ力学的研究を実施し,以下の成果を得た. 1.き裂を有する圧電積層材料の電気弾性・有限要素解析を行い,エネルギー解放率等の破壊力学パラメータに及ぼす分域回転及び負荷電場の影響を明らかにした. 2.(1)圧電セラミックスを対象に,MSP(改良型小型パンチ)試験・有限要素解析を行い,破壊荷重・MSPエネルギー・最大ひずみエネルギー密度に及ぼす180°,90°分域回転及び負荷電場の影響を解明した.また,有限要素解析と実験から得られたMSPエネルギーを比較・検討し,MSP試験片の分域回転領域を示して考察を加えた. (2)三層圧電積層片持ちはり(バイモルフ型アクチュエータ)の非線形曲げ試験・有限要素解析を行い,たわみに及ぼす分域回転及び負荷電場の影響を明らかにした.また,三層圧電アクチュエータを対象に,両端単純支持三点曲げ試験及び理論・有限要素解析を行い,変位・分域回転に及ぼす力学的・電気的負荷の影響を解明した. (3)内部電極を有する圧電積層材料の電極端近傍応力・電束密度を理論的に解明した.また,内部・表面電極を有する多層圧電アクチュエータの電極端近傍における電気弾性場集中に及ぼす印加電圧・分域回転の影響及び非線形挙動を理論的・実験的に解明した.さらに,円形電極の場合についても同様に解明し,考察を加えた. 3.圧電セラミックスのDT(ダブルトーション)試験を行い,破壊荷重に及ぼす負荷電場の影響を解明した.また,DT試験の有限要素解析を行い,破壊力学パラメータに及ぼす分域回転及び負荷電場の影響を解明して,実験結果に理論的検討を加えた.

  21. き裂を有する圧電複合材料の電気弾性力学に関する理論的研究

    成田 史生

    2000年 ~ 2001年

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    本研究は、圧電複合材料の電気破壊強度・機能設計に資することを目的に、き裂を有する圧電複合材料の電気弾性解析を行ったものである。本年度は、き裂の電気弾性解析モデルとして界面近傍の内部き裂、界面き裂等を設定し、圧電複合材料の電気破壊力学解析を行い、応力拡大係数・エネルギー解放率・エネルギー密度等の破壊力学パラメータに及ぼす分極・電場及び負荷(引張り・せん断)の影響を解明した。得られた成果を要約すると以下の通りである。 1.き裂を有する圧電積層材料の平面ひずみ電気弾性解析を行い、破壊力学パラメータに及ぼす電場の影響を検討しており、一部興味ある結果を得ている。 2.(1)円形圧電介在物が弾性母材に接合されている圧電複合材料を対象に、2個の対称界面き裂による面外断波散乱問題を理論解析し、電気破壊動力学的挙動を解明した。また、円振動数に対する動的応力拡大係数・動的エネルギー解放率を数値計算し、圧電特性の影響を考慮した。 (2)圧電繊維複合材料の電気破壊力学的挙動解明を目指し、円板状き裂を有する圧電円柱の電気弾性挙動について検討し、破壊力学パラメータに及ぼす電場の影響を解明・考察した。 (3)上記電気破壊力学解析結果を踏まえ、圧電繊維複合材料の電気破壊評価に関する基礎的研究を進め、一部興味ある結果を得ている。 3.分極方向が異なる2つの圧電セラミックスからなる界面き裂を有する圧電積層材料の電気弾性解析を行い、き裂先端近傍における電気弾性場の特異挙動解明に成功している。また、き裂を有する圧電複合材料の混合モード電気弾性挙動解明を目指して検討を進めており、一部興味ある結果を得ている。

  22. 先進圧電材料システムの電気破壊・変形挙動解明

    進藤 裕英, 成田 史生, 堀口 勝三

    提供機関:Japan Society for the Promotion of Science

    制度名:Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)

    研究種目:Grant-in-Aid for Scientific Research (B)

    研究機関:TOHOKU UNIVERSITY

    1999年 ~ 2001年

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    本研究は、先進圧電材料システムの破壊・変形挙動に及ぼす電場・波動場の影響解明に関する理論的・実験的研究を行ったものでる。すなわち、知的・電子材料システムの設計・開発及び安全性評価に資することを目的に、3年間の研究を実施し、以下の成果を得た。 1.き裂を有する圧電セラミックスの電気弾性解析を行い、応力拡大係数・エネルギー解放率・エネルギー密度・疲労き裂成長速度に及ぼす圧電特性・電場・力学的負荷(ひずみ制御・応力制御)の影響を解明した。また、き裂面電気的境界条件についても考察を加えた。 2.(a)圧電繊維複合材料の面外せん断波(SH波)散乱問題を理論解析し、複合材料中を伝播する有効平面SH波の位相速度・振幅減衰の円振動数依存性に及ぼす電場・界面すべりの影響を解明した。また、圧電繊維複合材料のSH波散乱解析を電場の影響を考慮して行い、介在物近傍の電気弾性場及び動的応力・電場集中の円振動数依存性を解明した。(b)圧電繊維複合材料に存在する界面き裂によるSH波散乱問題を理論解析し、動的応力拡大係数・動的エネルギー解放率・散乱断面積・電位の円振動数依存性に及ぼす界面剥離・圧電特性の影響を解明した。 3.圧電セラミックスの圧子圧入(IF : Indentation Fracture)・予き裂導入破壊(SEPB : Single-Edge Precracked Beam)試験を行い、破壊・変形特性に及ぼす電場の影響を解明した。また、有限要素解析を行い、応力拡大係数・エネルギー解放率に及ぼす電場の影響を解明して、実験結果に理論的検討を加えた。 4.圧電セラミックスの改良型小型パンチ(MSP : Modified Small Punch)試験・有限要素解析を行い、破壊時の荷重・変位及び臨界MSPエネルギー(破壊までに試験片に蓄えられるMSPエネルギー)に及ぼす電場の影響を解明した。また、IF・SEPB試験結果とMSP試験結果を比較・検討し、電気破壊靱性評価に考察を加えた。

︎全件表示 ︎最初の5件までを表示

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︎全件表示 ︎最初の5件までを表示