2009 年 117 巻 1365 号 p. 643-646
Highly oriented, Bi-substituted Ca3Co4O9(Ca2.7Bi0.3Co4O9) was processed by the rolling method and its thermoelectric properties were investigated. The electrical conductivity (σ), Seebeck coefficient (α), thermal conductivity (k) and ZT value at 870 K were 123.4 S/cm, 172.7 μV/K, 2.1 W/mK, and 0.152, respectively. The electrical conductivity was about 1.5 times higher than that of a conventionally sintered sample. This rolling process is a very powerful method to produce a plate-like particle orientation in a ceramic microstructure and will be useful in the mass production of thermoelectric elements in powder injection molding (PIM).