Since Ni-based superalloys are used in the gas turbines of jet engines, heat-resistant coatings are necessary. The heat-resistant coating consists of multiple layers of bond coat and top coat. During prolonged usage at high temperature, oxides formes between the bond coat and top coat. It has been known that the adhesion between the bond coat and the oxide is improved by Hf or Si addition, and that the durability of the coating material is improved. However, the mechanism of the improvement of adhesion is unknown. In this study, first principles calculations based on density functional theory were performed to estimate the interfacial energies between the bond coat and oxide with various reactive elements (RE). It was clarified that REs such as Hf and Si significantly reduce the interfacial energy, which is the origin of the durability improvement of thermal barrier coatings.

Created at: 2024-08-08 03:13:02 +0900 Updated at: 2025-12-24 06:55:10 +0900