Long-time ablation behavior of the multilayer alternating CVD-(SiC/HfC)3 coating for carbon/carbon composites

To improve the service life of carbon/carbon (C/C) composites under ultra-high temperature ablation environments (> 2200 degrees C), SiC/HfC coating with multi-layer alternating structure was designed and prepared on C/C composites by low-pressure chemical vapor deposition (LPCVD). The microstructure and phase compositions of the as-prepared and ablated coatings were investigated, and the influence of the multi-layer structure on the ablation behavior and thermal stress distribution of the coatings were analyzed as well. After ablation for 120 s, the (SiC/HfC)3 coating has better ablation resistance due to its multi-layer structure and the formation of Hf-Si-O sticky glass phase.

Automated summary

The SiC/HfC coating with multi-layer alternating structure prepared on C/C composites by LPCVD showed improved ablation resistance under ultra-high temperature environments, attributed to the formation of Hf-Si-O sticky glass phase and the multi-layer structure.