摘要
分析了炼钢转炉托圈连接螺栓早期断裂的原因。结果表明 ,开裂起源于加工时变截面过渡圆角的尖刀痕 ,经短程疲劳扩展后发生脆断。螺栓脆断是由于严重的冶金缺陷及组织不良 ,导致材料性能恶化。重新热处理后获得了良好的综合性能。
An investigation was made into one of the self adjustable bolts connecting the converter trunnion ring in a steel mill which broke after being in service for 13 months. The results showed that the fracture initiated in a heavy tool mark at a change in section, and propagated for a short distance as fatigue crack, then the remainder of the section fractured in a brittle manner. Brittle fracture of the bolt occurred because of the combined effect of a massive metallurgical defect plus a coarse mixed microstructure (bainite and martensite). Both higher strength and better impact toughness are obtained after re heat treatment of the bolts.
出处
《理化检验（物理分册）》
CAS
2000年第11期508-512,共5页
Physical Testing and Chemical Analysis(Part A:Physical Testing)
关键词
螺栓
疲劳断裂
过热
冶金缺陷
Bolt
Fatigue fracture
Overheated
Metallurgical defect
