Preparation, Sinterability, Electrical Transport and Thermal Expansion of Perovskite-Type La_0.8Ca_0.2CrO₃ Composites

Abstract

Perovskite-type was synthesized by two methods, the combustion method and conventional solid state reaction (SSR) method. The effect of synthesis methods on sinterability and physical properties of the ceramic were investigated. The results show that there are advantages of the combustion method in producing doped lanthanum chromites. Compared with the SSR method, the combustion method reduces the sintering temperature of La0.8Ca0.2CrO3, elevates the electronic conductivity and thermal expansion coefficient (TEC) of the ceramic, due to optimizing the microstructure. At the same densities level (–93%), the specimen synthesized by the combustion method reaches a superior electrical conductivity of 31.6 S·cm-1 and a compatible TEC of 10.7 × 10−6 K−1 at 800 °C.

Keywords

• perovskite-type La_0.8Ca_0.2CrO₃
• combustion method
• microstructure
• electrical conductivity
• thermal expansion coefficient (TEC)