Abstract
Carbon matrix of C/C composites were modified for the relaxation of thermal stresses between C/C composites and ceramic coatings. Porous C/C composites with various amounts of carbon matrix and porosity were prepared. Liquid silicon was impregnated into porous C/C composites and reacted chemically with carbon matrix to form silicon carbide. Thermal expansion of C/C composites could be controlled between 1.7 to 3.5×10-6/°C by altering the amount of silicon carbide in the matrix.