Thermal chemomechanical coupling behavior and analysis method of high-temperature thermal structural materials

The structural integrity of high-temperature materials is an important guarantee for the safety and reliability of hypersonic aircraft during service. Extreme service environments expose thermal structural materials to complex forces, extreme thermal, and strong oxidation, resulting in particularly prominent thermal chemomechanical coupling problems that directly affect material performance and equipment service life. This article systematically reviews the research progress in the field of thermal chemomechanical coupling of high-temperature thermal structural materials at home and abroad, focusing on four core directions. In terms of thermal chemomechanical coupling constitutive theory, starting from the early mechanics diffusion coupling model, the development of near equilibrium state full coupling theory was sorted out, and the obvious shortcomings of non-equilibrium state theory in describing thermal/diffusion fluctuations and chemical reaction pathways under extreme conditions were pointed out. In terms of experimental characterization techniques, the application status of ultra-high temperature testing platforms at home and abroad was compared and analyzed, and the unique advantages and application limitations of in-situ characterization techniques in capturing the dynamic coupling behavior of materials were deeply explored. In terms of multi-scale simulation and numerical calculation methods, the research status of molecular dynamics simulations and fully coupled finite element models covering mechanics, diffusion, and chemical reactions, as well as large deformation algorithms, has been summarized. In terms of failure analysis and fracture strength theory, the protective mechanism of oxide film and the influence of microstructure on the macroscopic strength of materials were elaborated, and it was pointed out that the fracture model considering the thermal chemomechanical coupling effect still needs further improvement. Finally, this article provides a prospect for theoretical, simulation, and experimental research on the thermal chemomechanical coupling of high-temperature structural materials.