High-temperature oxidation of non-zirconium materials for ATF

Abstract

Non-zirconium materials, such as silicon carbide (SiC) and FeCrAl alloys, have attracted interest for developing Accident-Tolerant Fuel (ATF) cladding systems owing to their superior hightemperature oxidation resistance. SiC offers excellent thermal stability, high-temperature properties, irradiation tolerance, and low activation, while FeCrAl alloys provide outstanding oxidation resistance in steam and air through a stable alumina (Al₂O₃) layer. This study examines their oxidation behavior under simulated severe-accident conditions. Microstructural changes and mechanical integrity after exposure were analyzed using scanning electron microscopy (SEM) and ring compression tests (RCT). The analysis revealed material-specific strengths and limitations, emphasizing the role of temperature and oxidation environment.