Aerothermal response of ceramic matrix composites to nitrogen plasma at temperatures above 2000 K

Carbon/silicon carbide composites are tested at surface temperature above 2000 K in a high-enthalpy nitrogen flow at 2000 Pa, generated by an inductively coupled Plasmatron. Their altered surface is analyzed using scanning electron microscopy. Comparisons with experiments in air plasma at similar heat flux and pressure conditions suggest that the sole presence of nitrogen prevents the occurrence of temperature jump effect observed for this class of materials in flows containing oxygen reactants. Optical emission spectroscopy measurements near the surface confirm a lower volatility for the material tested in nitrogen compared to air.