Dynamic oxidation mechanism of carbon fiber reinforced SiC matrix composite in high-enthalpy and high-speed plasmas
Lingwei Yang, Xueren Xiao, Liping Liu, Jie Luo, Kai Jiang, Xinxing Han, Changhao Zhao, Jun Zhang, Guolin Wang
Abstract
Abstract This work employed an inductively coupled plasma wind tunnel to study the dynamic oxidation mechanisms of carbon fiber reinforced SiC matrix composite (C f /SiC) in high-enthalpy and high-speed plasmas. The results highlighted a transition of passive/active oxidations of SiC at 800–1600 °C and 1–5 kPa. Specially, the active oxidation led to the corrosion of the SiC coating and interruption of the SiO 2 growth. The transition borders of active/passive oxidations were thus defined with respect to oxidation temperature and partial pressure of atomic O in the high-enthalpy and high-speed plasmas. In the transition and passive domains, the SiC dissipation was negligible. By multiple dynamic oxidations of C f /SiC in the domains, the SiO 2 thickness was not monotonously increased due to the competing mechanisms of passive oxidation of SiC and dissipation of SiO 2 . In addition, the mechanical properties of the SiC coating/matrix and the C f /SiC were maintained after long-term dynamic oxidations, which suggested an excellent thermal stability of C f /SiC serving in thermal protection systems (TPSs) of reusable hypersonic vehicles.