High pressure synthesis of new super hard materials in the boron suboxide system and their functional evaluation
| Project/Area Number |
12450273
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Composite materials/Physical properties
|
|---|
| Research Institution | Nagoya University |
|---|
Principal Investigator |
ITOH Hideaki Nagoya University, Research Center for Advanced Waste and Emission Management (ResCWE), Professor, 難処理人工物研究センター, 教授 (60109270)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
SASAI Ryo Nagoya University, Research Center for Advanced Waste and Emission Management (ResCWE), Assistant Professor, 難処理人工物研究センター, 助手 (60314051)
|
|---|
| Project Period (FY) |
2000 – 2002
|
| Project Status |
Completed (Fiscal Year 2002)
|
| Budget Amount *help |
¥13,000,000 (Direct Cost: ¥13,000,000)
Fiscal Year 2002: ¥3,100,000 (Direct Cost: ¥3,100,000)
Fiscal Year 2001: ¥4,700,000 (Direct Cost: ¥4,700,000)
Fiscal Year 2000: ¥5,200,000 (Direct Cost: ¥5,200,000)
|
|---|
| Keywords | high pressure sintering / boron suboxide / super-hard material / sintering material / microvickers hardness / fracture toughness / composite / B-C-N-O系超硬物質 / 金属ホウ素化合物 / 超高圧・高温合成 / 複合焼結体 / 研削・研磨工具 |
|---|
| Research Abstract |
New super-hard materials in the boron suboxide system, which contains oxygen atom or light mmetals in the cavity of the rhombohedral unit cell of icosahedral boron clusters, were sintered in composite with other super-hard material under high pressure. The mechanical properties of these composites were investigated along with their chemical and electrical properties. The main results and conclusions in the project term were summarized as follows.
1. High pressure sintering of boron suboxide (B_6O) and its composite with diamond
B_6O is known as a super-hard material with high chemical stability and also a target material for thermoelectric conversion recently. However, this material is so brittle and difficult to sinter that its actual application as an industrial material is delayed. In the present study, we prepared the sintered compact of B_6O by high pressure sintering of B_6O powder synthesized from B_2O_3 and amorphous boron, and elucidated the mechanical and thermal properties of B_6O single phase sintered compact. In order to enhance the fracture toughness of the compact without decreasing its hardness, the binary composite system of B_6O and diamond was investigated. In case of using fine-grained diamond powder, a superl-hard composite with an increased fracture toughness was prepared and its electrical conductivity at room temperature was as high as the magnitude of 10^<-3> S/cm.
2. High pressure sintering of AlMgB_<14> and its composite with other super-hard material
AlMgB_<14> is also a super-hard material with analogous crystal structure to B_6O and expected to exhibit higher mechanical strength. Single phase sintered compact of AlMgB_<14> was prepared originally under high pressure using the powder synthesized in our laboratory. This compact showed the hardness as high as B_6O, though the fracture toughness was similarly low. Presentation of the composite systems of AlMgB_<14> with B_6O or TiB_2 resulted in higher hardness, hut lower fracture toughness.
|
Report
(4 results)
Research Products
(10 results)
