1999 Fiscal Year Final Research Report Summary
Development of high-strength fiber for ultra high-temperature application by fast directional solidification method : control of microstructure
| Project/Area Number |
10555254
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| Research Category |
Grant-in-Aid for Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Section | 展開研究 |
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| Research Field |
Metal making engineering
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| Research Institution | TOHOKU UNIVERSITY |
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Principal Investigator |
FUKUDA Tsuguo Institute for Materials Research, Tohoku University, Professor, 金属材料研究所, 教授 (30199236)
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| Co-Investigator(Kenkyū-buntansha) |
WAKU Yoshiharu Yamaguchi Research Institute, Japan Ultra-high Temperature Materials Research Institute, Chief Researcher, 山口研究所, 主幹研究員
SHIMAMURA Kiyoshi Institute for Materials Research, Tohoku University, Research Associate, 金属材料研究所, 助手 (90271965)
YOSHIKAWA Akira Institute for Materials Research, Tohoku University, Research Associate, 金属材料研究所, 助手 (50292264)
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| Project Period (FY) |
1998 – 1999
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| Keywords | oxide eutectic / high-temperature strength / reinforcement fiber |
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| Research Abstract |
In this study, we applied a shape-control technique on the micrometer-scale (fiberization) for the development of new ceramic in-situ composite materials having high strength up to high temperature. The eutectic materials YィイD23ィエD2AlィイD25ィエD2OィイD212ィエD2(YAG)/AlィイD22ィエD2OィイD23ィエD2(sapphire) and GdAlOィイD23ィエD2(GAP)/sapphire were studied with the aim of reducing the microstructure from micro-scale to nano-scale in a controlled way. In particular, to develop a thermally stable reinforcement fiber which can be used at 1700℃ in air atmosphere, we investigated the conditions for stable growth of high quality, homogeneous fibers with well-controlled diameter and microstructure.
1. Microstructure control : We have clarified the relative orientations of the eutectic components YAG and sapphire, and GAP and sapphire, by TEM electron diffraction analysis. This will play a key role in the elucidation of the growth mechanism of the eutectic crystal.
2. Fiber diameter control : The meniscus was well controlled by the end shape of the crucible, and we found a strong relation between the shape and the fiber diameter. Based on this observation, we were able to grow thin fibers as small as 150μm in diameter.
3. High temperature strength : We tested tensile strength at room temperature in air atmosphere and at 1500℃ in Ar, and measured fundamental physical properties of the grown eutectic fibers such as thermal expansion coefficient etc. Tensile strengths reached 930MPa at room temperature and 570MPa at 1500℃.
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Research Products
(24 results)
