2017 Fiscal Year Final Research Report
Elucidation of characteristic fatigue behavior of nano-scale metals and construction of its mechanical foundation
Project/Area Number |
15H02210
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Research Category |
Grant-in-Aid for Scientific Research (A)
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Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Materials/Mechanics of materials
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Research Institution | Kyoto University |
Principal Investigator |
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Co-Investigator(Kenkyū-buntansha) |
中村 篤智 名古屋大学, 工学研究科, 准教授 (20419675)
嶋田 隆広 京都大学, 工学研究科, 准教授 (20534259)
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Project Period (FY) |
2015-04-01 – 2018-03-31
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Keywords | Fatigue / Micron / Nano / Metal / Tension-copmpression / In situ observation / Single crystal / Copper |
Outline of Final Research Achievements |
In this project, we aimed to examine the tension-compression fatigue behavior of micron- and nano-scale metals. Target material was copper single crystal. In low cycle fatigue, strain burst occurred during tensile deformation in the first cycle. In the compressive half cycle, a nano-scale extrusion was brought about owing to localized reverse slip. Extrusions/intrusions were grown with increasing of number of cycles, resulting in nano-scale cracking. This fatigue behavior was significantly different from that of bulk counterparts where micron-scale extrusions/intrusions with characteristic dislocation structure formation are grown. A special loading device, which was developed in this project, enabled us to realize high cycle fatigue experiment. In the experiment, although noticeable strain burst did not occur, the nano-scale extrusion/intrusion grew from several hundred cycles. On the basis of these results, we clarified the specific fatigue mechanism of micon- and nano-scale metals.
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Free Research Field |
微小材料強度学、金属結晶学
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