一、故障简况涡轮轴发动机准备装备油气分离器时,发现压气机二级转子叶片中四片折断(叶尖掉角).一片有宏观可见裂纹。故障叶片断裂形态如图1至图3所示。从18号故障折断叶片断口可以看出(图1),宏观贝壳状疲劳环清晰可见,疲劳源起始于化学损伤处(点腐蚀坑),属于典型的振动疲劳断裂故障。经振型及动测试验表明,属于由发动机压气机一级静子叶片尾流激振(频率5620～ First, the breakdown briefing Turboshaft engine ready to equip oil and gas separator, found two compressor blades in the second break (tip angle.) There is a macro-visible cracks. Failure blade fracture morphology shown in Figure 1 to 3. As can be seen from the fault fracture of No. 18 fracture (Fig. 1), the macroscopic shell-like fatigue ring is clearly visible. The source of fatigue starts at the point of chemical damage (pitting corrosion pits) and is a typical vibration fatigue fracture failure. The vibration mode and dynamic test show that belongs to the engine compressor first stage stator vortex wake (frequency 5620 ~