CAJ | 학술논문

主要针对贯穿螺栓的断裂，对其化学成分、力学性能、金相组织、断口进行了分析。断裂的主要原因是贯穿螺栓的冶金质量不佳。螺栓内含有大量的非金属夹杂物，有的呈链状分布在螺纹表面，同时螺栓内又有严重的成分偏析。当此二种不利因素叠加时，螺栓在螺纹工作面非金属夹杂物聚集处先发生剥落，然后向内伸展，当裂纹走过疲劳区，螺栓的截面大幅减小，仅剩的截面承受不了交变应力时，便发生瞬间断裂。
주요침대관천라전적단렬，대기화학성분、역학성능、금상조직、단구진행료분석。단렬적주요원인시관천라전적야금질량불가。라전내함유대량적비금속협잡물，유적정련상분포재라문표면，동시라전내우유엄중적성분편석。당차이충불리인소첩가시，라전재라문공작면비금속협잡물취집처선발생박락，연후향내신전，당렬문주과피로구，라전적절면대폭감소，부잉적절면승수불료교변응력시，편발생순간단렬。
This paper analyzed the components, mechanical property, microstructure and fracture of the fractured through bolt. The main reason of the fracture was the poor metallurgical quality. The through bolt not only had a lot of nonmetallic inclusions which some had formed chains on the thread surface, but also composition segregation was serious. When both of the two disadvantages worked together, on the thread working face where the nonmetallic inclusions gathering place was peeled off at the first time, and then extended internal, when the crack came to the fatigue area cased the bolt’s working face decrease. And when the remaining working face could not bear the alternating stress,the through bolt was fractured instantaneous.