Oxidation behavior of MoSi2 and Mo(Si, Al)2 coated Mo–0.5Ti–0.1Zr–0.02C alloy

MoSi2 and Mo(Si, Al)2 coatings were prepared on Mo–0.5Ti–0.1Zr–0.02C alloy using pack cementation process. Oxidation studies revealed that Mo(Si, Al)2 coating had a much superior oxidation resistance in the temperature range from 400 to 900 °C, where pest disintegration of MoSi2 occurs due to internal oxidation. The growth kinetics of Al2O3 layer formed on Mo(Si, Al)2 coating was much slower than that of SiO2 layer formed on MoSi2 coatings during oxidation.