1992 Fiscal Year Final Research Report Summary
High Temerature Plasticity of Metal/Ceramic Interface Free of Reaction Product Layer and Enhanced by Nonstoichiometry
| Project/Area Number |
02452242
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| Research Category |
Grant-in-Aid for General Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Research Field |
金属材料(含表面処理・腐食防食)
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| Research Institution | University of Tokyo |
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Principal Investigator |
ISHIDA Yoichi University of Tokyo, Department of Materials Science, Professor, 工学部, 教授 (60013108)
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| Co-Investigator(Kenkyū-buntansha) |
MORI Minoru University of Tokyo, Institute of Industrial Science, Associate Professor, 生産研, 助教授 (30134646)
SUGA Tadatomo University of Tokyo, Research Center for Advanced Science and Technology, Associ, 先端研, 助教授 (40175401)
ICHINOSE Hideki University of Tokyo, Dept. of Materials Science, Research Associate, 工学部, 助手 (30159842)
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| Project Period (FY) |
1990 – 1992
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| Keywords | Metal / Ceramic Joining / Reaction Product Free Interface / Nonequilibrium Composition / High Temperature Plasticity / Stress Relaxation / Interface Structure / Superconductivity / High Resolution Electron Microscopy |
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| Research Abstract |
This year the research of plasticity at metal/ceramic joined interfaces has been concentrated with following three systems where the interfere is free of the reaction product layer.(1) Ni/Si_3N_4 system
Using a high temperature goniometer stage mounted in a high resolution electron microscope, thermal stress induced deformation near the Ni/Si_3N_4 reaction product free interface has been observed "in situ" by changing the specimen foil temperature. The motion of interface dislocation has been observed, but the major mechanism of thermal stress relaxation has been the motion of the lattice dislocation in nickel grain. The interface acted as the site of dislocation absorption rather than emission. Chemical analysis of the fractured interface indicated the segregation of sintering additives at the interface between nickel base superalloy and Si_3N_4. (2) Bi_2Sr_2Ca_2Cu_3Ox/Ag/Bi_2Sr_2Ca_2Cu_3Ox system
In order to use Bi-superconducting oxide as a Josephson device, silver thin layer is useful. The AC V-I characteristics indicated the performance of the [001] twist bicrystal is good at certain misorientation where the interface structure is ordered. (3) C_<60>/graphite system
Carbon 60 is face centered cubic at ambient temperatures and the plastic deformation is like that of metals. The C_<60> molecules were produced either by vacuum deposition or pulled up by LB method to mount C_<60> on the basal plane of graphite. The observation by STM showed that the interface is not like that of Ag/Bi_2Sr_2Ca_2Cu_3Ox where the allignment of monolayer silver atoms parallel to the a axis of the superconducting oxide was pronounced.
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