1996 Fiscal Year Final Research Report Summary
NEW EVALUATION METHODS FOR MICRO-R-CURVE OF ADVANCED CERAMIC COMPOSITES
| Project/Area Number |
07650795
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Composite materials/Physical properties
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| Research Institution | TOKYO INSTITUTE OF TECHNOLOGY |
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Principal Investigator |
YASUKA Kouichi TOKYO INSTITUTE OF TECHNOLOGY,FACULTY OF ENGINEERING,ASSOCIATE PROFESSOR, 工学部, 助教授 (20191306)
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| Co-Investigator(Kenkyū-buntansha) |
TANABE Yasuhiro TOKYO INSTITUTE OF TECHNOLOGY,MATERIALS AND STRUCTURES LABORATORY,ASSOCIATE PROF, 応用セラミックス研究所, 助教授 (70163607)
MATSUO Yohtaro TOKYO INSTITUTE OF TECHNOLOGY,FACULTY OF ENGINEERING,PROFESSOR, 工学部, 教授 (70016608)
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| Project Period (FY) |
1995 – 1996
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| Keywords | CERAMIC COMPOSITES / FRACTURE TOUGHNESS / MICRO-R-CURVE / NEW EVALUATION METHOD |
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| Research Abstract |
A new evaluation method for micro-R-curve of advanced ceramic composites was proposed based on controlled surface flaw method (CSF method). A fracture mechanical model was developed to theoretically discuss the influence of interaction force between crack faces, residual stress around a Vickers indent, initial crack length and shape of a surface crack on micro-R-curveby CSF method. This model was verified with experimental results of glass, polycrystalline alumna, polycrystalline silicon nitride and tetragonal zirconia polycrystals. In case of polycrystalline silicon nitride, a rising micro-R-curve was measured and a bridging stress betwen crack faces was also estimated. In case of tetragonal zirconia polycrystals, micro-r-curve was not measured because residual stress was not eliminated by polishing larger than three times depth of the Vickersindent. We conclude that the new evaluation method can provide micro-R-curve for the materials that residual stress around a Vickers indent can be eliminated by polishind larger than three times depth of the indent.
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