Improvement in Specific Electric Resistance of Bi1.5Pb0.5Sr1.7Y0.5Co2O9-δ by Texture Development

Thermoelectric oxide Bi1.5Pb0.5Sr1.7Y0.5Co2O9- δ is produced by sintering method. Uniaxial compression deformation is performed on the oxide under various strain rates at 1113K, close to the melting temperature. After deformation, density, microstructure, texture and thermoelectric characteristics such as specific electric resistance and Seebeck coefficient, are experimentally studied. Deformation mechanism is examined by stress change test. It is found that the oxide plastically deforms mainly by the motion of dislocations at the present temperature, resulting in an increase in density as well as the development of texture. It is concluded that the specific electric resistance extensively decreases by the high temperature compression deformation through densification and texture development.