Heat dissipation of carbon shell in ZrC–SiC/TaC coating to improve protective ability against ultrahigh temperature ablation

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 ZrO₂ 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.