High-temperature oxidation of NiCrAlY/(ZrO2–Y2O3 and ZrO2–CeO2–Y2O3) composite coatings

Metal/ceramic coatings of Ni–22Cr–10Al–1Y/ZrO2–8Y2O3 and Ni–22Cr–10Al–1Y/ZrO2–25CeO2–2.5Y2O3, which were prepared by the air plasma spray method, were oxidized at 900, 1000, and 1100 °C in air. The major oxidation product was α-Al2O3, which was formed by the reaction of inwardly penetrating oxygen ions with Al at the metal/ceramic phase boundaries. The oxidation of Ni and, moreover, Cr also occurred to a certain extent.