Oxidation Behavior of Alumina-Forming Alloys in CO2-H2O Environment

The oxidation behavior of wrought and dispersion-strengthened alumina-forming FeCrAl and Fe-Al alloys were evaluated in a CO₂-H₂O atmosphere at 1100°C.  This environment simulates a potential future high temperature oxy-fired superheater condition.  Alumina-forming alloys typically perform better than chromia-forming alloys in the presence of water vapor and high carbon activities at high temperature.  However, under these conditions, a significant increase in scale exfoliation and oxidation rate was observed compared to dry air experiments.  Additional characterization is needed to understand these observations.