The Forming Process of Liquid Phase during Liquid Phase Sintering of SiC Ceramic

High temperature real time observation equipment was used to obtain the shrinkage curve of SiC ceramic with sintering additive of Al2O3-Y2O3 in liquid phase sintering.TG-DTA-MASS technique and in-situ X-ray diffraction technique were used to measure the weight loss before and after liquid phase formation and the phase transformation during the sintering process of SiC.The results show the liquid phase formed far below the eutectic temperature of the sintering additive because the eutectic temperature of Al2O3-Y2O3 declined due to the existence of SiO2 on the surface of SiC.The formation of the liquid phase caused rapid weight loss of the samples.