预测腐蚀疲劳寿命的概率方法

PROBABILITY APPROACH FOR PREDICTION OF CORROSION FATIGUE LIFE

在建立航空发动机铝合金构件点状腐蚀和腐蚀疲劳裂纹扩展模型的基础上 ,将铝合金叶片的机械腐蚀特性和由环境诱导的电化学行为看作是随机量或随机过程 ,提出腐蚀疲劳寿命预测的概率方法 ,利用重要随机变量的累积分布函数 ,估算寿命累积分布函数 ,预测腐蚀疲劳寿命。

Corrosion problem is increasingly became one of the most important factor that work on the life and structure reliability of aero-engine which enlist in navy. The model of pitting corrosion and corrosion fatigue crack growth of Aluminium alloys parts of aero-engine in ocean environment is developed and the probability approach for prediction of corrosion fatigue life is proposed in this paper. The mechanism corrosion characteristic and the electrochemistry behavior abducted by environment is taken as random variable or random process. By using the cumulative distribution function for each key random variable, the cumulative distribution function for the lifetime is estimated and the corrosion fatigue life is predicted. The method is applicable to the prediction of reliability and durability of aero-engine blades.