Influence of doping elements X (X= Hf, Zr, Y, Re, Pd, Ir) on the structural stability and tension property of α-Al₂O₃/PtAl₂-S interfaces

Pt-Al coatings are promising materials for protective materials for turbine blades in new-generation aero-engines. Therefore, it is worth noting that the interface stability and tension property between Pt-Al and the oxide layer, prolonging coating service time. However, systematic studies of doping elements effects on interface adhesion of α-Al₂O₃/PtAl₂ with and without impurity S are still lacking. In this paper, the site preference of the six elements (Hf, Zr, Y, Re, Pd, and Ir) in the PtAl₂ alloy, effects of doping elements on the interface adhesion and tension properties of the α-Al₂O₃/PtAl₂-S interface are further explored, performing the first-principles calculation method. Considering comprehensively, Y doping has an excellent enhancement effect on the static interface adhesion and dynamic tensile strength, regardless of whether impurity element S exists in the α-Al₂O₃/PtAl₂ interface. This study will provide necessary theoretical guidance for the composition design of Pt-Al coating and the research of new metal protective coating materials.