Microstructure and cyclic ablation behaviour of a Si–Mo–Ti protected C/C composites by a two-step method

Abstract

ABSTRACT A two-step method combining reactive melt infiltration and slurry coating was employed to fabricate completely protected C/C composites. Microstructure and cyclic ablation behaviour of the composites were investigated. Results show that a SiC transition layer can be obtained when ceramic coating generated during the infiltration process is preserved as part of the substrate for the slurry coating process. The SiC transition layer can improve the cyclic ablation resistance of the composites. The transition layer is the thickest when the chemical composition of the mixed powder used in the slurry coating process is n(Si):n(Mo):n(Ti) = 8:1:3. Such composites have the best cyclic resistance with 0.055 mg/cm2 mass loss in each ablation cycle.