Anti-ablation properties of ZrB2 modified carbon/phenolic composites in plasma wind tunnel

Improving the ablative resistance of carbon/phenolic (C/Ph) composites is an urgent need in the field of thermal protection of hypersonic vehicles. In this paper, novel C/Ph composites are fabricated by introducing different contents of ZrB 2 ceramic particles, and the anti-ablation properties of the composites are tested in plasma wind tunnel. Under mainstream conditions with enthalpy of 21.84 MJ/kg, heat flux of 1.6 MW/m 2 , and pressure of 1.6 kPa, the effects of ZrB 2 ceramic content on the thermal stability, linear ablation rate and surface temperature of C/Ph composites are further analyzed. The maximum ablative surface temperature is positively correlated with the content of ZrB 2 . As the ZrB 2 content increases, the back face temperature of the materials decreases gradually, while the linear ablation rate increases slightly after a significant decrease. When the ablation time is 50 s, The linear ablation rate of the sample with 7% ZrB 2 content is the lowest (0.0184 mm/s). These dates of the plasma wind tunnel test could provide a reference for applications of C/Ph composites. The oxidation of ZrB 2 in the materials contributes significantly to improving its anti-ablation properties in severe environments. Accordingly, optimizing the ZrB 2 content enables the development of high-performance C/Ph composites with enhanced thermal properties, and reduced ablation rates, making them well-suited for thermal protection applications.