Lanthanum chromite-based ceramics, separators containing same and solid electrolyte fuel cells using separators

摘要

Lanthanum chromite-based ceramics represented by the general formula (La1-xSrx)a(Cr1-yCoy)bO3 where 0.02 <1><6> (atm) for 10 hours relative to that of products applied with a heat treatment at 1000 DEG C in air, and having a relative density of 90% or greater, in which conductivity sigma 1000,air at 1000 DEG C in air and conducivity sigma 1000,red at 1000 DEG C in a reducing atmosphere at an oxygen partial pressure of 1 x 10<-><1><5> (atm) satisfy the following equation: 10 <1>cm<-><1>) and 1 <1>cm<-><1>> heat expansion coefficient alpha from 50 DEG C to 1000 DEG C satisfies the following equation: 9.8 x 10<-><6> <6> (1/K), and having a 4-point bending strength at a room temperature of 10 (kgf/mm<2>)or greater according to JIS R1601. Lanthanum chromite system ceramics are dense, having a good conductivity, less temperature dependence of the heat expansion coefficient, decreased dimensional change rate and excellent dimensional stability.