基于断口分析的机车铸造牵引座焊后疲劳失效机制研究
打开文本图片集
中图分类号：U270 文献标志码：A
Research on Fatigue Failure Mechanism of Locomotive Casting Traction Seat After Welding Based on Fracture Analysis
Zhu Tao'，Qi Hongrui²，Tai Wanqiu²，Zhang Fan'，Wang Chao'，Xiao Shounel （1.State Key LaboratoryofRailTansit Vehicle System，Southwest Jiaotong University，Chengdu61oo31，China; 2. CRRC Datong Co.，Ltd.，Datong 037038，China）
Abstract： Aiming at the problem of high crack rate in key positions of cast traction seats for railway locomotives during long-term service，a study was conducted on the post-weld fatigue failure mechanism at key positions of cast traction seats based on fracture analysis.Firstly，a experimentallyvalidated finite element model of the tractionseat was established，and it was determinedthat thereisasignificantstressconcentrationareaat the large arc of the base of the traction seat under standard traction braking loads.Then，a high cycle fatigue test was conducted on the traction seat based on the standard load spectrum，reproducing the initiation and propagation process of macroscopic cracks in the stress concentration area. Finally，fracture analysis，scanning electron microscopy （SEM） observation，metallographic examination，and energy dispersive spectroscopy （EDS） were performed on the fatigue crack failure area，indicating the presence ofobvious welding repair marksand heat-treated microstructure in the crack area.Theresearch results indicate that the fatigue cracking failure of the traction seat is the result of the combined effect of stressconcentration at the base arcand defects introduced by welding repair. It is important to focus oncontrolling the casting qualityat the large arc of the baseand avoid welding repairs.The research can provide theoretical guidance for the safe and eficient operation ofrailway freight and the maintenance and repairof parts.
Key Words： locomotive casting traction seat; high cycle fatigue test; fracture analysis; fatigue failure
Citation format： ZHU T， QI HR，TAI W Q，et al. Research on fatigue failure mechanism of locomotive casting traction seat after welding based on fracture analysis[J].JournalofEast China Jiaotong University，2O25，42（4）： 29-36.
重载列车有着载重大、编组辆数多的特点，在铁路货运系统中有着优势。（剩余9905字）
