Oxidation characteristics of Fe22Cr5Al3Mo-xNb alloys in high temperature steam

Abstract The oxidation behaviors of Fe22Cr5Al3Mo-xNb (x=0.5, 1.0, 2.0 wt%) alloys under simulated loss of coolant accident (LOCA) conditions at 1000 and 1200 ℃ were investigated. The results revealed that fine granular oxides and a ridged oxide film were formed on the FeCrAl alloys at 1000 and 1200 ℃, respectively. The oxide film was composed of α-Al2O3, α-Cr2O3 and a trace amount of FeO at 1000 ℃ but only consisted of α-Al2O3 at 1200 ℃ due to volatilization of Fe and Cr oxides. Nb addition decreased the weight gains and improved the oxidation resistance of FeCrAl alloys under simulated LOCA condition.