某发动机涡轮盘低循环疲劳试验故障分析

The Failure Analysis of a Test Gas Turbine Disk

某型燃气涡轮转子试验件在进行低循环疲劳试验时,试验件出现损坏。本文采用断口分析、金相组织检测等手段对其失效性质及裂纹萌生原因进行分析。结果表明:后挡板破裂性质为疲劳,裂纹源位于沟槽底部,机加痕迹是形成疲劳源的主要原因。为了提高挡板的疲劳寿命,需要严格控制沟槽底部的加工质量、提高该处的表面粗糙度。

The test rotor of a type of gas turbine was failed in low circle fatigue test.Measures such as fracture surface analysis and metallic structure inspection were used to analyze the type failure and reason of crack generation.The analysis show that the crack is firstly generated at slot of the baffle disk,which result in local over loaded.The reason for fracture is fatigue,and the fatigue crack start from the bottom of the slot,which is origin from the cutting mark of machining.Higher quality control of the slot bottom by increase surface roughness is required to increase the baffle disk low circle fatigue life.