화학공학소재연구정보센터
Materials Research Bulletin, Vol.47, No.8, 2067-2071, 2012
Investigation on the calcining condition and sintering temperature of perovskite-type La0.7Ca0.3CrO3 complex oxides by a combustion method
Perovskite-type La0.7Ca0.3CrO3 composite oxides were synthesized by a combustion method. The calcining condition of the synthesized powders and sintering temperature of ceramic specimens were studied. It was found that a pure perovskite structure was direct acquired in the combustion ash and the fine morphology (similar to 100 nm) was observed in the sample calcined at 600 degrees C. In view of the relative density, microstructure and electrical conducting properties of the sintering ceramics at different temperatures, the preferred sintering temperature was ascertained to be 1300 degrees C, at which the sample attains a high relative density of 96.8%, showing an electrical conductivity of 53.6 S cm(-1) at 800 degrees C and much lower activation energy of 0.122 ev. Compared with La0.7Ca0.3CrO3 synthesized by the conventional solid state reaction method, that synthesized by the combustion method exhibits fine morphology and superior sintering activity, effectively lowering the sintering temperature and enhancing electrical conducting properties of the material. (c) 2012 Elsevier Ltd. All rights reserved.