| Project/Area Number |
24760532
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| Research Category |
Grant-in-Aid for Young Scientists (B)
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| Allocation Type | Multi-year Fund |
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| Research Field |
Physical properties of metals
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| Research Institution | Tohoku University |
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Principal Investigator |
CHEN Chunlin 東北大学, 原子分子材料科学高等研究機構, 助手 (50614989)
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| Project Period (FY) |
2012-04-01 – 2014-03-31
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| Project Status |
Completed (Fiscal Year 2013)
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| Budget Amount *help |
¥4,550,000 (Direct Cost: ¥3,500,000、Indirect Cost: ¥1,050,000)
Fiscal Year 2013: ¥2,210,000 (Direct Cost: ¥1,700,000、Indirect Cost: ¥510,000)
Fiscal Year 2012: ¥2,340,000 (Direct Cost: ¥1,800,000、Indirect Cost: ¥540,000)
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| Keywords | 表面 / 界面 / 粒界物性 / 動的ナノ計測 / 変形破壊力学 |
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| Research Abstract |
Understanding of origin of materials fracture is the key point to prevent their damages, and also is an important subject of materials science. Through a combined study of in-situ TEM nanoindentation and advanced microscopy, we investigate the microstructure evolution of ceramics during nano-deformation, and study the mechanism of materials fracture.
There is no obvious plastic deformation during the nanoindentation of 4H-SiC. The emission of dislocation also cannot be seen. A micro-crack is formed and propagates along on the (0001) crystal plane. After unloading, dislocations are observed at the tip of the crack. It suggests that the dangling bonds on the surfaces of crack rebound and the healing of crack take place. Effects of grain boundaries on the mechanical properties of cubic BN have been studied. It is found that Sigma9 and sigma3 GBs of cubic BN are inclined to trap oxygen, which lowers the GB adhesion energies significantly, and greatly reduces the hardness of cubic BN.
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