Thermal Response And Oxidation Of Tyranno Fibre-Reinforced Si-Ti-C-0 Matrix Composites For A Thermal Protection System In High-Enthalpy Dissociated Air

The thermal response and oxidation of Tyranno Lox-M fibre-reinforced Si-Ti-C-O matrix composites in high-enthalpy dissociated air was investigated in an arc jet facility. The maximum surface temperature reached 1310-1670 deg C. Catalytic re-combination of oxygen and nitrogen on the composite surface under dissociated air was not significant. Surface recession was insignificant below 1600 deg C surface temperatures and above 5 kPa of oxygen partial pressure at the stagnation point. Passive-to-active oxidation transition of the composite agreed with Balat's theory for monolithic silicon carbide. A glass sealant prevented active oxidation of the composite for short-time exposures.