Heat dissipation of carbon shell in ZrC–SiC/TaC coating to improve protective ability against ultrahigh temperature ablation
Yuyu Zhang, Xuemeng Zhang, Hongkang Ou, Bozhe Wang, Jia Sun, Qiangang Fu
Abstract
To efficiently decrease ablation heat accumulation and improve the ability of ZrC–SiC/TaC coatings to protect carbon/carbon (C/C) composites, a thermally conductive nanonetwork with a ceramic@carbon core–shell structure was designed and constructed. Polymer-derived SiC/TaC with a graphene carbon shell was synthesized and introduced into a ZrC coating by supersonic atmospheric plasma spraying (SAPS). Graphene shell paths increased the heat transfer capability by lowering the surface temperature to approximately 200 °C during oxyacetylene ablation. The heat dissipation of the graphene shell in the ZrC–SiC/TaC@C coating reduced the volatilization of low-melting-point phases and delayed the sintering of ZrO<sub>2</sub> particles. Thus, the graphene shell in ZrC–SiC/TaC@C coating decreased the mass and linear ablation rates by 91.4% and 93.7% compared to ZrC–SiC/TaC coating, respectively. This work provided a constructive idea for improving the ablation resistance of the coatings by incorporating carbon nanomaterials as a function of heat dissipation.