某高速离心式压缩机叶片在运行过程中发生断裂。通过对叶片断口及冲蚀表面进行宏观观察、材料化学成分分析、力学性能测试、断口扫描电镜观察、能谱分析和显微组织分析, 找出了叶片的断裂失效原因。结果表明: 压缩机叶片断裂主要是由于级间冷却器流体布局设计不合理, 致使叶片在运行时不断受到冷却器管束铝翅片微粒高频脉动的冲刷磨损作用, 在局部叶片迎风表面形成垢层, 产生了高周疲劳载荷, 使位于其对称位置的叶片在相对薄弱的顶部萌生裂纹并逐渐扩展, 最终导致叶片高周疲劳断裂失效; 另叶片材料冲击韧度低加速了疲劳裂纹的扩展。

Impeller blades of high-speed centrifugal aircompressor fractured during operation process, and failure reasons was investigated by means of visual examination, chemical compositions analysis, mechanical properties testing, SEM observation, EDS analysis and metallographic examination. The results show that the main cause for fracture failure of the compressor blades was due to the high speed aluminum particles. The particles came from inter-stage cooler fins because of poor shell fluid layout design. A thick fouling layer was formed on the surface of the blades by the aluminum particles which brought about high frequency fatigue load to the opposite located blades and cracks initiated on the tip of the blades. Therefore the blade failed due to high frequency fatigue and fretting wear. The low impact toughness of the blade material also accelerated the crack propagation.