摘要
汽车焊接桥壳在台架试验中发生早期断裂。对桥壳的开裂位置、断口的宏微观特征进行观察分析,对桥壳材料的化学成分、硬度和金相组织进行了测试和分析,结合有限元模拟方法,分析桥壳受力。结果表明:断裂发生在下板托焊缝端部,断口呈现明显的疲劳特征;造成断裂的主要原因是板托焊缝端部的应力水平较高,以及焊缝存在未焊透缺陷加剧应力集中,名义应力较大,诱发了疲劳疲劳裂纹源的萌生,提出了提升焊接质量、优化桥壳附件设计等措施,对延长桥壳的疲劳寿命具有指导意义。
Fracture occurred to a automobile welding axle housing in the fatigue test. In order to find out the failure mode and cause, macro and micro observation, chemical composition and hardness testing, metallographic examination and finite element analysis were carried out. The results show that the fracture is fatigue fracture occurring at the weld edge of the lower shell supporter. There was higher stress at the weld edge, and the incomplete penetration aggravated the stress concentration, which was the main cause for the initiation of fatigue crack. Based on the analysis results, some measures were put forward, such as improving welding quality and optimizing the design of the axle housing.
出处
《失效分析与预防》
2015年第2期118-122,共5页
Failure Analysis and Prevention
关键词
焊接桥壳
断裂
疲劳
有限元
welding axle housing
fracture
fatigue
finite element
