摘要
某型号强度级别为10.9级的球架锚固螺栓发生断裂,该螺栓已使用了4～5年,通过材料化学成分分析、材料力学性能测试、断口分析以及金相组织检验等,分析了锚固螺栓断裂失效的原因。结果表明,锚固螺栓断裂方式为疲劳断裂,疲劳源位于螺纹根部应力集中区,为线性起裂源;弯拉工作应力叠加了一定的冲击波动载荷是螺栓发生疲劳断裂的主要原因,防护层破坏后螺纹底部发生腐蚀,在一定程度上促进了疲劳裂纹的形成。
The anchor bolts of grade 10.9 are broken in the course of operation,the fracture of the bolt occur after 4~5 years service. Through the analysis of the chemical composition,the mechanical properties,the fracture analysis and the metallographic examination,the reasons for the failure of the bolt of the hub are analyzed. The results show that the bolt fracture is fatigue fracture,fatigue source is located in the whorl root stress concentration zone,which is the linear crack source;bending work stress superposition impact wave load is the main reason for the fatigue fracture of the bolt,the protective layer after the destruction of thread bottom corrosion in a certain extent promoted the formation of fatigue crack.
作者
许晓明
XU Xiao-ming(Chang'an Campus,Shaanxi Preschool Teachers College,Xi'an 710100,Shaanxi,China)
出处
《合成材料老化与应用》
2019年第2期104-107,共4页
Synthetic Materials Aging and Application
关键词
锚固螺栓
疲劳断裂
工作应力
防护层
anchor bolt
fatigue fracture
working stress
protective layer
