高熵稀土氧化物热障涂层材料弹性及热物性的第一性原理研究OA

Continuous fiber-reinforced silicon carbide ceramic matrix composites utilized in hot-section components of high thrust-to-weight ratio aero-engines require protection via thermal/environmental barrier coatings(T/EBCs).To develop novel rare-earth oxide thermal barrier coating materials with low thermal conductivity,compatible thermal expansion coefficients,and excellent high-temperature phase stability,introduction of a high-entropy design concept offers a promising approach and opportunity for composition design and performance optimization.Addressing the challenges of structural modeling and property prediction for complex high-entropy ceramic systems,this study firstly introduces a novel high-entropy ceramic modeling strategy based on the special quasi-random structure(SQS)method.This strategy facilitates rapid prediction of complex ceramic properties while maintaining computational accuracy.Subsequently,crystal structures,elastic properties and thermophysical characteristics of four high-entropy rare-earth oxide materials are predicted and compared by integrating first-principles calculations.This research particularly elucidates regulatory effects and atomic-scale origins of different rare-earth compositions and Hf doping on the material's low thermal conductivity performance.The research results provide scientific insights and fundamental data for theoretical simulation and material selection design of T/EBCs for aero-engine hot-section components.