不锈钢泵叶轮叶片断裂原因

Reasons for the fracture of stainless steel pump impeller blades

某316L不锈钢泵叶轮叶片发生断裂现象。采用宏观观察、化学成分分析、扫描电镜分析、金相检验和显微硬度测试等方法分析了叶片断裂的原因。结果表明:叶轮叶片表面存在明显的凹坑和划痕,凹坑和划痕处产生应力集中,在工作载荷和叶片振动产生的激振力作用下,应力集中处萌生裂纹并不断扩展,最终导致叶片发生疲劳断裂。

A 316L stainless steel pump impeller blade broke.The reasons for blade fracture were analyzed using macroscopic observation,chemical composition analysis,scanning electron microscopy analysis,metallographic examination and microhardness testing.The results show that there were obvious pits and scratches on the surface of the impeller blades,and stress concentration occurred at the pits and scratches.Under the action of the working load and the excitation force generated by blade vibration,cracks appeared at the stress concentration and continued to propagate,ultimately led to fatigue fracture of the blades.