Effect of Cr and Y2O3 on the oxidation behavior of Co-based oxide dispersion strengthened superalloys at 900 °C

In order to study the effect of Cr and Y2O3 addition on the oxidation behavior of novel Co-20Cr-10Al (wt.%) oxide dispersion strengthened (ODS) superalloys, an isothermal oxidation test was carried out at 900 °C in air. The addition of Cr altered the oxide scale from the multilayered scale with an external Co oxide/CoAl2O4 and an inner Al2O3 to a single Al2O3 scale. Y2O3 addition increased oxidation mass gain slightly but improved spallation resistance of the external Al2O3 scale.