Comparative analysis of CoCrAlY coatings at high-temperature oxidation behavior using different reinforcement composition profiles

The oxidation behaviour of plasma-sprayed carbides and oxides reinforced composite CoCrAlY coatings at 700 degrees C was examined in this paper. CoCrAlY was reinforced with Al2O3 + YSZ, CeO2, WC-Co, Cr3C2-NiCr individually to produce four different coatings. SEM, EDS, and XRD are used to analyse the oxide scales formed during the oxidation process on the surface of the coating. From the results, it is found that all of these coatings had a parabolic weight gain, suggesting the existence of a shielding oxide scale on the surface, whereas changes in total weight gain are observed. The oxidation resistance of CoCrAlY + Al2O3 + YSZ coating is better and exhibits 28% less weight gain than other coatings. During oxidation, coating shows slow scale growth of kinetics due to thermodynamically stable Al2O3. The CoCrAlY + 2% CeO2 coating showed the lowest oxidation resistance of all the coatings.