某涡轮叶片热障涂层的寿命预测方法

基于NASA发展的CoatLife软件中推荐的应力 寿命建模方法,研究了某涡轮叶片热障涂层寿命预测方法。通过在寿命模型中引入氧化增质量,并考虑氧化动力学,实现了寿命模型与高温氧化效应的关联。由于寿命模型中的疲劳强度系数是时间和半径的函数,从而可以应用于实际结构中的不同几何形状,并考虑了时间相关的退化效应。计算结果表明,随着最高温度或疲劳强度系数的增加,涂层的循环寿命和时间寿命均会减少。通过对某涡轮叶片在设计温度场下的涂层寿命预测结果表明,循环时间为1h条件下叶片前缘1/2叶高处涂层剥落寿命大约336 h,与实际叶片涂层失效在300~400h之间吻合。 

Thermal barrier coating life prediction method for a turbine blade

Based on the stress life model developed by NASA and integrated in CoatLife software, the life prediction method of the thermal barrier coating on a turbine blade was investigated. Through the introduction of the oxidation mass gain in the life model, the oxidation dynamic was considered， and the high temperature oxidation effect can be introduced in the life model. Because the fatigue strength coefficient was the function of service time and geometric radius, the arbitrary geometry in real structures and the time dependent deterioration effect could be covered. The calculation results showed that the cycle life and the time life of the coating decreased with the increase of the maximum temperature or fatigue strength coefficient. Based on the design temperature field, the life of a turbine blade coating was predicted. The results showed that the spalling life the coating at the half height of the leading edge was about 336h when the cyclic time was 1h, and this agreed well with the real coating life between 300h and 400h.