Research progress on self-healing YSZ-based thermal barrier coating of aero-engine

The thermal barrier coatings (TBCs) is the key technology of next-generation aero-engine and the self-healing capability in the high-tempature environment is vital for the performance improvement. The failure mechanism of yttria stabilized zirconia (YSZ) based TBCs under high-temperature environments was analyzed; the formation of thermally grown oxides and the effect of crack extension on YSZ coatings was attached great importance. The mechanism and research progress of crack self-healing under high temperature of self-healing thermal barrier coatings containing self-healing agents SiC, TiC, and MoSi₂ was reviewed, and the modification mechanisms and the effect on YSZ coatings of the addition of self-healing agent on various properties of YSZ coatings, such as thermal conductivity, thermal cycle life, and mechanical properties was illustrated in detail. The challenges faced by different self-healing agents in practical applications and future prospects were discussed. The research can provide important theoretical basis and engineering application reference for material design and optimization of new generation self-healing thermal barrier coatings with long-life and high reliability.