低压三级工作叶片振动疲劳试验裂纹失效分析

Crack failure analysis of low-pressure three-stage blade vibration fatigue test

为了解决航空发动机低压三级工作叶片振动疲劳失效问题,从叶片材质、机加工工艺和叶片结构尺寸等角度,对叶片振动疲劳考核不合格原因进行分析。结果表明,低压三级工作叶片裂纹性质为高周疲劳,符合振动疲劳试验情况下的破坏模式。通过对叶片材质、机加工工艺的分析表明,材质、机加工工艺不是造成构件振动疲劳强度低的主要原因。改善叶片截面之间厚度尺寸参数,可有效降低叶片的应力,提高叶片的振动疲劳强度,符合发动机对叶片的使用要求,叶片失效问题得到了有效解决。

In order to solve the problem of aero-engine low-pressure three-stage blade vibration fatigue failure,the reasons for the unqualified blade vibration fatigue assessment have been analyzed from the perspective of blade material,machining technology and blade structure size.The results show that the crack nature of the low-pressure three-stage blade is high-cycle fatigue,which conforms to the failure mode under the vibration fatigue test.The analysis of the blade material and machining process shows that the material and machining process are not the main reasons for the low fatigue strength of the components.Improving the thickness and dimension parameters between the blade sections can effectively reduce the stress of the blade and increase the vibration fatigue strength of the blade,which meets the requirements of the engine for the use of the blade.Thus in this way,the problem of blade failure has been effectively solved.