Thermophysical Properties of Short Carbon Fiber/SiC Multilayer Composites Prepared by Tape Casting and Pressureless Sintering

Csf/SiC multilayer composites for thermal conductivity (TC) test in three directions were successively prepared by tape casting and pressureless sintering. After 1500°C/5 h oxidation treatment, short carbon fibers were oxidized which produced many pores. However, a core area, which was composed by short carbon fiber, SiC, and few SiO2, was still observed. TC properties of Csf/SiC multilayer composites were highly anisotropic. The TC was decreased with the increase in fiber amount. Csf/SiC multilayer composites demonstrated the highest TC along the tape casting direction and the lowest TC through the thickness direction, which is favorable for thermal protection purpose.