| Project/Area Number |
11650691
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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 |
Inorganic materials/Physical properties
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| Research Institution | Akita University |
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Principal Investigator |
TAIMATSU Hitoshi Akita University, Faculty of Engineering and Resource Science, Professor, 工学資源学部, 教授 (60125721)
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| Co-Investigator(Kenkyū-buntansha) |
ATSUMI Taroh Akita University, Faculty of Engineering and Resource Science, Research Associate, 工学資源学部, 助手 (40282157)
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| Project Period (FY) |
1999 – 2000
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| Project Status |
Completed (Fiscal Year 2000)
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| Budget Amount *help |
¥2,800,000 (Direct Cost: ¥2,800,000)
Fiscal Year 2000: ¥500,000 (Direct Cost: ¥500,000)
Fiscal Year 1999: ¥2,300,000 (Direct Cost: ¥2,300,000)
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| Keywords | TiB_2 / TiC / TiN / ZrB_2 / ZrN / displacement reaction / reaction sintering / 固相置換反応 / 固相反応 / 超硬材料 / ホウ化物 / チッ化物 |
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| Research Abstract |
Reaction processes in the B_4C-Ti, BN-Ti and BN-Zr systems were examined for determining the most suitable reaction temperature and holding time for the syntheses of TiB_2-TiC-C, TiB_2-TiN and ZrB_2-ZrN composites with fine microstructure. For the TiB_2-TiC-C composites, their densification was tried by reactive hot pressing.
For reactive hot pressing of powder mixtures of B_4C and Ti at 2000℃, different reaction products were formed by varying the Ti/B_4C mixing ratio x : B_4C-TiB_2-C at 0<x<2, TiB_2-C at x=2, TiB_2-TiC-C at 2<x<3 and TiB_2-TiC at x=3. Relative density had the minimum value 97.0% at x=2. Except for this mixing ratio, every sintered body was highly dense and had a relative density more than 98.4%.
For the reaction between Ti and BN at 1100℃, TiB was first formed as an intermediate product and then TiB_2 was formed by the reaction between TiB and BN.N/Ti ratios of TiN_x in TiB_2-TiN composites were a little lower than those estimated from the mixing ratios. Because of this phenomenon, a little amount of BN always remained after reaction. The synthesis of a perfect TiB_2-TiN composite will need excessive addition of Ti.
For the reaction between Zr and BN at 1100℃, the reaction ceased after a reaction time of 144 h. Syntheses in an Ar stream prefer to those in vacutun or in vacuumized capsule. The nonstoichiometry of ZrN_x decreased with the reaction time.
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