Abstract:A novel SiC-ZrB₂ coating was prepared using a two-step technique by slurry-sintering and chemical vapor reaction on carbon/carbon (C/C) composites. The SiC-ZrB₂ coating was composed of the scattered ZrB₂ phase and the continuous SiC phase. It was observed that a good adhesion was built between the coating and the C/C composites. The SiC-ZrB₂ coating samples exhibited a better ablation resistance in comparison with the uncoated C/C composites. The SiO₂-ZrO₂ barrier layer, the heat dissipation of the gaseous products and the pinning effect of ZrO₂ all contributed to the good ablation resistance of the SiC-ZrB₂ coated composites.

Key words: ablation; coating; microstructure; carbon/carbon composites