Reliability analysis of thermal barrier coatings on turbine guide vanes of a certain type of aero-engine

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.