| Project/Area Number |
12305049
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (A)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Material processing/treatments
|
|---|
| Research Institution | Osaka University |
|---|
Principal Investigator |
ITO Mikio (2002) Osaka University, Graduate School of Engineering, Assistant Professor, 大学院・工学研究科, 助手 (00294033)
永井 宏 (2000-2001) 大阪大学, 大学院・工学研究科, 教授 (80029206)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
KATSUYAMA Shigeru Osaka University, Graduate School of Engineering, Associate Professor, 大学院・工学研究科, 助教授 (00224478)
井藤 幹夫 大阪大学, 大学院・工学研究科, 助手 (00294033)
真島 一彦 大阪大学, 大学院・工学研究科, 助教授 (60029270)
|
|---|
| Project Period (FY) |
2000 – 2002
|
| Project Status |
Completed (Fiscal Year 2002)
|
| Budget Amount *help |
¥34,010,000 (Direct Cost: ¥30,500,000、Indirect Cost: ¥3,510,000)
Fiscal Year 2002: ¥5,200,000 (Direct Cost: ¥4,000,000、Indirect Cost: ¥1,200,000)
Fiscal Year 2001: ¥10,010,000 (Direct Cost: ¥7,700,000、Indirect Cost: ¥2,310,000)
Fiscal Year 2000: ¥18,800,000 (Direct Cost: ¥18,800,000)
|
|---|
| Keywords | Thermoelectric material / Thermal conductivity / Mechanical alloying / Polymerized complex method / Fine particle / Figure of merit / Seebeck coefficient / Electrical resistivity / 微粒子分散 / 液相焼結 / 比抵抗 / 粉末治金 / 熱電材料 / ナノコンポジット / 熱起電力 / 電気抵抗 / 粉末冶金 / 傾斜材料 |
|---|
| Research Abstract |
Several kinds of fine particles, such as insulating conductive and/or metallic conductive fine particles, were dispersed in the matrix of thermoelectric materials. The thermoelectric materials used in this study were β-FeSi_2, CoSb_3 and several thermoelectric oxides, and the effects of these fine particles addition of the thermoelectric performance, especially the thermal conductivity. In the case of the β-FeSi_2, it was found that a densely sintered body with the high figure of merit could be synthesized by SiC fine particle dispersion and Cu powder addition. The addition of rare earth oxides, which have low thermal conductivity and good chemical stability, was significantly effective on reducing thermal conductivity and increasing Seebeck coefficient, especially when Y_2O_3 powder was added. The improvement of Seebeck coefficient and the results of the Hall coefficient measurement suggest that the solution of a small amount of the rare earth element into the Fe site of the β-FeSi_2 matrix occurs. In the case of the CoSb_3, the dispersion of the metallic FeSb_2 and NiSb fine particles was quite effective on reducing the electrical resistivity, as well as the thermal conductivity, resulting in the significant improvement of the thermoelectric performance. The thermoelectric oxides, ZnO and Na_xCo_2O_4 were synthesized by the polymerized complex method (PCM). The PCM was found to promote the solution of doping element compared to the conventional solid state reaction method, expanding the possibility of enhancement of thermoelectric properties by doping. When the impurity phases precipitated, they were finely dispersed in the matrix, indicating that the PCM is also effective on reducing the thermal conductivity.
|
