High-temperature oxidation and nitridation of substoichiometric zirconium carbide in isothermal air

The influence of nitrogen on the oxidation behavior of hot-pressed zirconium carbide was investigated using a flow-tube furnace at temperatures ranging from 1000 to 1600 °C. Mass gain, oxide formation characteristics, and oxide transitions were evaluated at various experimental conditions. Differences in oxidation behavior across the range of temperatures investigated show both kinetic and microstructural dependence with implications pointing to this materials efficacy in ultra-high temperature applications. Results suggest that at temperatures above 1400 °C, although oxidation mechanisms remain dominant, nitridation and reduction mechanisms may be appreciable enough to require consideration. Supporting discussions regarding polymorphism and microstructural influences are outlined.