Oxidative Ablation Behavior of W-Coated C/C Composites Prepared by Chemical Vapor Deposition with Heat Treatment

To improve the ablation resistance of C/C composites, tungsten (W) coating is applied by chemical vapor deposition (CVD) technology on C/C composites. Results show that the coatings are dense, with a thickness of about 400 μm. After heat treatment at a temperature of 1500 °C for 1 h, the main component of coating is W₂C. Additionally, a dense WC layer forms on the surface of pyrolytic carbon (PyC). The sample subjected to heat treatment remains relatively intact after ablation at 3000 °C for 60 s, with a mass and linear ablation rate of 1.83 × 10⁻⁵ g s⁻¹ and 3.03 × 10⁻⁵ cm s⁻¹, respectively. The high-temperature stability of WC formed on PyC and the filling of fiber gaps to prevent oxygen penetration are the main reasons for the improved ablation resistance of W-coated C/C composites.