Elucidating the role of preferential oxidation during ablation: Insights on the design and optimization of multicomponent ultra-high temperature ceramics

Abstract Multicomponent ultra-high temperature ceramics (UHTCs) are promising candidates for thermal protection materials (TPMs) used in aerospace field. However, finding out desirable compositions from an enormous number of possible remains challenging. Here, through elucidating the role preferential oxidation ablation behavior multicomponent UHTCs via thermodynamic analysis and experimental verification, correlation between composition performance was revealed aspect thermodynamics. We found that metal components can be thermodynamically divided into preferentially oxidized component (denoted as M P ), which builds up a skeleton oxide layer, laggingly L fills skeleton. Meanwhile, driven gradient concentration forms layer. Based on these findings, strategy pre-evaluating developed, provides preliminary basis design UHTCs.