Research progress in potential high-entropy ceramic thermal barrier coating materials

Thermal barrier coating (TBC) materials are an important method to provide thermal protection and prolong service life for aero-engines and gas turbines. In recent years,various kinds of high-entropy (HE) rare earth oxides have emerged in the exploration of novel thermal barrier coating materials, in order to obtain thermal, mechanical, high temperature phase stability, sintering corrosion resistance and other properties better than single principal rare earth oxides through HE effect on the thermodynamics and kinetics of hysteresis diffusion effect, the structure of the lattice distortion effect and "cocktail" effect on the performance. The thermal, mechanical and other performances of HE rare-earth zirconates,cerates,hafnates,phosphates,tantalates,niobates,etc. were summarized and analyzed in comparison with the performance of the corresponding single phases to investigate the various factors affecting the performance. Finally,it was pointed out that in the future, it may be possible to combine experiments with first-principles calculations to select high-entropy ceramic thermal barrier coating materials with superior comprehensive performance; at the same time, extending high-entropy to complex components or medium-entropy ceramic thermal barrier coating materials is also an important development direction.