Chemical reaction at high temperature and high pressure VII : solid state reaction of silicon with graphite to form silicon carbide and its stability

Abstract

The yield of SiC in the solid state reaction between Si and graphite powder has been studied at temperatures of 800～1, 100℃ under pressures of 10～50kb. The temperature of commencement of reaction is represented by 0.7×Tw°K (melting point of Si under pressure). The yield of SiC increases with increasing temperature and pressure, so that the rate determining step would be in the reaction process. The α--β transformation of SiC has been observed under pressure and it has been concluded thermodynamically that the β form SiC would be the stable species in the experimental conditions.