扇形板螺栓断裂失效分析

Fracture Analysis of Sector Plate Bolt

某扇形板螺栓在装配过程中发生断裂,采用宏观观察、磁粉探伤、热酸蚀试验、化学成分分析、显微观察和电镜观察等手段对扇形板螺栓的断裂原因进行了分析。结果表明,该扇形板螺栓在墩头时因过烧造成晶界熔化变宽而使强度降低,从而导致该螺栓早期断裂。

The fracture of sector plate bolt occurs in assembling process. The fracture cause of sector plate bolt is analyzed by means of macroscopic observation, magnetic particle inspection, thermal etching experiments, chemical composition analysis,microstructure observation and scanning electron microscope. The results show that the grain boundary of the bolt is melted due to overburning while mounding its head,and which reduces its strength and results in early fracture of the bolt.