吊环螺钉断裂失效分析

Fracture failure analysis of eye bolt

某工厂在进行重物吊装作业时,吊环螺钉发生了断裂,文中通过对断口宏观样貌分析、金相分析、化学成分分析、碳化层硬度测试,并结合断裂发生时的工况及受力状态,对断裂的原因进行了分析,结果表明该吊环螺钉的断裂属于疲劳断裂。同时,吊环螺钉的加工缺陷,如螺钉根部粗糙度及加工痕迹,以及螺钉材料中的非金属夹杂、螺纹处脱碳等因素,也加剧了断裂起始点的应力集中,使得裂纹更容易生成并拓展,最终导致断裂。

When lifting heavy objects,the eye bolt of a factory broke.Through macroscopic appearance analysis,metallographic analysis,chemical composition analysis,hardness test of carbonized layer,combined with working conditions and stress state when the fracture occurred,causes are analyzed.Results show that the fracture of eye bolts is caused due to fatigue.Meanwhile,machining defects of eye bolts,such as the roughness and machining marks of bolt roots,the inclusion of nonmetal in bolt materials,decarburization at threads and other factors,also can aggravate the stress concentration at the starting point of fracture,which makes it easier to produce and expand cracks,eventually leading to fracture.