超高圧焼結により作製したβ-FeSi_2系熱電材料の微細構造と熱電特性の異方性 Microstructure and the Anisotropic Thermoelectric Properties of β-FeSi_2 Sintered under High-Pressure
β-FeSi<SUB>2</SUB> was sintered under high-pressure/ temperature conditions of 3 GPa and 700-1400°C for 30 min using a belt-type high-pressure equipment. The material showed anisotropy due to heterogeneous distribution of pressure, however, the X-ray diffraction analysis did not reveal crystallographic orientation. The microstructure showed grain orientation along the direction perpendicular to the pressing direction. Such orientation was remarkable in the sample solidified from the melt. It was suggested that the development of microstructure was important factor in optimizing the thermoelectric properties. The formation and the phase stability of β-FeSi<SUB>2</SUB> under high-pressure condition were also discussed.
粉体および粉末冶金 44(1), 39-43, 1997-01-15
Japan Society of Powder and Powder Metallurgy