The growth mechanism of oxide scale with Pt on NiCoCrAlY coating in water vapor at 1050∘C

In this study, we focus on the oxidation behavior of the oxide scale with Platinum (Pt) on free standing NiCoCrAlY coating in air with water vapor at high temperature. The Pt layer is deposited on the NiCoCrAlY coating surface by electroplating, and then heat treatment at 1000[Formula: see text]C with Argon (Ar) protection. Cycle oxidation of the oxide scale with Pt is conducted in air and air with water vapor at 1050[Formula: see text]C. The results indicated that the spinels (NiCr2O4) are formed on the surface of the alumina scale in air and air with water vapor. However, this kind of spinel is inhibited in the air with water vapor and the scale on the coatings with Pt presents a good adherence during oxidation process. The thermal stress and crack initiation and propagation will be discussed.