摘要
对某烟气轮机的动叶片榫齿接触痕迹特征、组织和受力进行综合分析。结果表明,榫齿裂纹为起始应力较大的疲劳裂纹,受力最大的第三榫齿和榫槽接触不均匀,局部磨损严重导致发生磨蚀萌生裂纹。榫齿各部位的混晶以及晶界连续粗大碳化物膜加速了裂纹的萌生与扩展。另外,材料在高温燃气环境下易发生腐蚀,也是导致榫齿失效的诱发因素。
The contacting trace, microstructure and stress state of fractured gas turbine tenon were analyzed. The results show that it was fatigue fracture on account of higher initial stress. The third tenon which endures the biggest stress makes non-uniform contact with the splineway. The serious concentrated wear leads to crack. The carbide film which is massive and consecutive on the grain boundary and the mischcrystal accelerate the initiation and propagation of the crack. Moreover, the material corrosion in fuel gas at high temperature is also an inducing factor for the failure.
出处
《失效分析与预防》
2006年第4期34-37,26,共5页
Failure Analysis and Prevention
关键词
烟气轮机
榫齿
疲劳
腐蚀
晶界
gas turbine
tenon
fatigue
corrosion
grain boundary
