Ablation behavior of C/SiC composites in plasma wind tunnel

The ablation behavior is crucial to the application of carbon fiber reinforced silicon carbide (C/SiC) composites in thermal protection systems of spacecraft to enter the atmosphere or to cruise hypersonically in near space. Plasma wind tunnel is a suitable tool to simulate the service conditions of space vehicles. In this study, we systematically studied the ablation behaviors of C/SiC composites in plasma wind tunnel. The oxidation behavior of C/SiC composites in plasma is discussed. The results indicated that the oxidation under atomic oxygen condition dominated at low heat flux and stagnation pressure; however, rapid recession mechanism by sublimation and decomposition of SiC was observed at high heat flux and stagnation pressure. The temperature jump phenomenon during the ablation performed under high heat flux and stagnation pressure was attributed to the exposure of the carbon fibers to the plasma flow after consumption of the SiC coatings.