Significant improvement of the self-protection capability of ultra-high temperature ceramic matrix composites

The oxidation behaviour of C/ZrB-SiC with different fibre architectures, manufactured by slurry impregnation, polymer infiltration and mild pyrolysis, was investigated. Short term oxidation tests in air were performed for 1 min and 5 min at 1500 °C and 1650 °C in a bottom loading furnace. Microstructure, oxide scale thickness and composition were analysed by SEM/EDS/XRD. Results indicated that a good dispersion of ZrB particles in the polymer derived SiC(O) matrix promoted the formation of compact scales filling surface holes left by fibre oxidation. 20-30 vol% of ZrB in the material was found a good compromise between lightness and oxidation resistance.