【摘要】 M30×410 mm的双头螺柱在使用中发生了断裂。通过宏观检查、断口扫描、金相检查、化学成分测定、力学性能检测、硬度梯度检测等方式对断裂原因进行分析。结果表明,螺柱的显微组织、化学成分、力学性能正常;螺柱断口具有典型的疲劳断裂特征,其断裂形式为疲劳断裂;螺柱断裂的主要原因是螺柱杆部表面产生的微裂纹在交变应力的持续作用下逐步扩展,最终造成断裂。更多还原

【Abstract】 M30 × 410 mm of the stud bolt was fracture during running. The fracture reason of the stud was analyzed by macro observation,fracture scanning,metallographic examination,chemical composition analysis,mechanical properties test,hardness gradient test and so on.The results show that the microstructure,chemical composition and mechanical properties of the stud bolt are all normal; the fracture of the bolt is characterized by fatigue fracture; the main reason of the bolt fracture is that the micro crack is generated on the bolt surface,thus producing fatigue crack which extends further under the continuous alternate stress and finally resultes in fatigue fracture.更多还原