To investigate the influencing factors of CMAS corrosion resistance in rare-earth zirconates, seven low-, medium-, and high-entropy rare-earth zirconates RExZO (RE = Y, Ho, Dy, Er, Gd, Yb, Tm; x = 1-7) were prepared, and their CMAS corrosion behaviors at 1 300 ℃ were systematically studied. Results indicate that rare-earth zirconate materials undergo dissolution damage upon contact with CMAS at high temperatures, accompanied by the formation of a new apatite phase. The high-entropy structure facilitated the development of a dense reaction layer composed of apatite and fluorite phases through a “dissolution-reprecipitation” mechanism, significantly reducing the maximum infiltration depth from 80.6 μm for RE1ZO to 30.9 μm for RE7ZO (a 61.7% reduction). Influenced by ionic radius variations, dissolved rare-earth elements exhibited gradient diffusion into the apatite and fluorite phases. Correlation analyses reveal a significant positive relationship between corrosion depth and optical basicity difference, while showing significant negative correlations with configurational entropy and atomic size disorder. First-principles calculations and XPS results further confirm that high configurational entropy reduces the Gibbs free energy and oxygen vacancy concentration of rare-earth zirconates while enhancing elemental binding energy, thereby improving structural stability. Based on these findings, an optimization strategy for designing CMAS-resistant rare-earth zirconates is proposed: priority should be given to material combinations featuring low optical basicity difference, high configurational entropy, and high atomic size disorder.

The reliability of the thermal barrier coating on the turbine guide blades of a certain civil aviation engine was studied, the blade surface temperature distribution model based on operating conditions, and the coating failure model based on temperature distribution were established. Moreover, the failure probability of the thermal barrier coating on the turbine guide blades at different service times and temperatures was calculated by Monte-Carlo simulation, the turbine guide blades’ service life was predicted and compared with the actual service results. The results show that the maximum failure probability of the thermal barrier coating is located at the leading edge of the turbine guide blade and the blade basin area. With 60% failure probability as the limit of complete failure, the average life of the thermal barrier coating in the leading edge region of the blade is only 3 857 h, the average life of the leaf basin region is 7 584 h, and the average life of the backside and trailing edge regions of the blade is more than 10⁴ h under the action of hot air flow. The agreement between the simulated service reliability and the actual inspection results of the turbine guided blades with the change of service time always stays above 60%, which proves that the reliability evaluation method used has credibility and practicality.