Effect of the Impact Compression on the Synthesis of Silicon Carbid

Abstract

The process of SiC synthesis during impact compression of silicon and carbon black powdered mixtures is investigated. Shock wave treatment of mixtures is carried out in cylindrical protective ampoules and the shock wave is generated by projecting the outer shell. The variation of C interaction with Si and SiC with the composition of the starting charge and its density is investigated. Thermal effects of the impact compression and exothermic reaction of silicon with carbon and the temperature of shock wave synthesis are determined. The assessment is made subject to the variation of Si silicon melting parameters and SiC formation enthalpy with the pressure. It is established that, during shock compression, the melting of silicon is accompanied with coalescence of Si particles that inhibits the interaction of Si with C and reduces the SiC yield at high Si content in the mixture. An optimal composition of the mixture providing the highest SiC yield is found.