发动机涡轮叶片断裂故障分析

Fracture Failure Analysis on Engine Turbine Blade

发动机在工作过程中突然停车,检查发现低压涡轮转子叶片全部损伤,高压涡轮叶片均齐根折断。通过对高低压涡轮叶片断口特征进行宏观检查分析,确定了首断件及其断裂性质为疲劳断裂;对首断件叶片断口进行显微分析,研究了断裂特征和疲劳扩展情况;断裂的原因为叶片上下缘板总间隙在使用过程中变大,阻尼效果变差,叶片异常振动,离心应力叠加振动应力,致使叶片在工作过程中断裂。

An engine of an aircraft suddenly stopped working, the damage of all the low-pressure turbine blades and the fracture from roots of all the high-pressure turbine blades were found after checking up. The first broken blade was confirmed after fracture macro analysis on all the low-pressure and high-pressure turbine blades, and the character of the blade fracture was fatigue fracture. By fracture micro analysis on the first broken blade, fatigue characteristic and development process of the crack were researched. The cause of the blade fracture was due mainly to the fact that the larger total gaps of up-marginal and under-marginal lead to abnormal vibration of the blade, so centrifugal stress with vibration stress made the blade break in the work process.