| Abstract Scope |
Due to its excellent high-temperature properties and stability, silicon carbide (SiC) is being considered for applications in high-temperature gas reactors, light-water reactors, and fusion platforms. In air-ingress accident scenarios, structural SiC components may be subjected to hot air in excess of 1000 °C. SiC-coated surrogate fuel particles were oxidized in oxygen-based mixtures of gases with oxygen partial pressure ranging from 0.0002 to 0.2 atm and temperatures ranging from 1000 to 1600 °C. The oxidized particles were characterized via scanning electron microscopy (SEM), focused ion beam (FIB), transmission electron microscopy (TEM), and atom probe tomography (APT). Various microstructural features were studied in the oxide scale, including surface roughness, scale growth kinetics, and devitrification behavior, corresponding to different oxygen partial pressures, oxidation temperatures, and times. The diffusion behavior of carbon, oxygen, and silicon were analyzed with respect to oxidation temperature. Insights into the mechanisms of SiC oxidation were obtained. |