Fabrication of reaction-bonded SiC ceramics by slip casting of SiC/C suspension

The influence of particle size and size distribution on slip casting performance of SiC and SiC/C suspension was investigated. Two kinds of commercial grade SiC powder and petroleum coke powder were used as the starting powder. The results showed that suitable particle size distribution is helpful to obtain low viscosity and relative high packing density. Smaller particles were used to prevent sedimentation velocity of larger particles. Ternary suspension containing petroleum coke and two kinds of silicon carbide powder exhibited higher viscosity than binary suspension containing only two kinds of silicon carbide powder. The right amount of petroleum coke could lead to suitable viscosity for slip casting and high flexural strength. The maximum flexural strength of sintered products was 274 ± 15 MPa in this work.