摘要
某机组低压末级叶片在运行过程中发生断裂。采用化学成分分析、力学性能检测和显微组织检验及用X射线法分析叶片的残余应力等方法对断裂叶片进行了分析。结果表明:疲劳裂纹起源于一个机械缺口,裂纹源在交变应力和残余应力的共同作用下不断扩展,导致叶片疲劳断裂。
The low pressure last stage blade of certain unit fractured during operation. The fracture reason was analyzed by means of the test methods for chemical composition, mechaniced performance and metallurgical structure of blade steel. The results showed that the fatigue crack initiated, from a mechanical gap. Analysis on residual stress in X-ray showed that the residual stress was very high at crack origin area. The crack origin growed to fatigue fracture forced by alternating stress and residual stress together.
出处
《理化检验（物理分册）》
CAS
2009年第2期121-123,共3页
Physical Testing and Chemical Analysis(Part A:Physical Testing)
关键词
叶片
疲劳
断裂
残余应力
blades
fatigue
ffacture
residual stress
