LAUSR

Abstract Three-dimensional carbon fiber preform reinforced mullite (C/Mullite) composites have been prepared through the sol-impregnation-drying-heating route in our previous studies. To further optimize the performance of C/Mullite composites, a PyC-SiC double-layer interfacial coating was introduced by polymer pyrolysis in this paper. The effects of PyC-SiC interfacial coating on the mechanical properties and thermal shock resistance of C/Mullite composites were investigated. It was found that the PyC-SiC interfacial coating played a positive role in protecting carbon fiber, weakening interfacial bonding and alleviating thermal mismatch between fiber and matrix. Consequently, both flexural strength and fracture work of C/Mullite composites were increased by more than 40%, and the thermal shock resistance in air was also improved.