Preparation of Carbon/Ceramic Composite Materials by Use of Raw Coke (Part 8)

Abstract

Carbon-based composites with dispersed β-SiC and B4C particles were prepared by normal pressure sintering. The spherical β-SiC particles with a diameter of 1μm in the dense matrix of carbon grew into rods with a diameter of 3 to 5μm and a length of up to 50μm by heat-treatment above 2300°C. The anisotropic growth of SiC did not occur when the matrix contained less than one percent B4C, but the anisotropic growth rate increased with increasing amount of B4C. Dimensional change of the composites caused by the growth of SiC rods was less than 5vol%. The composites were toughened hy a crack deflection mechanism caused by SiC rods dispersion.