华东交通大学学报2025，Vol.42Issue(4)：29-36,8.
基于断口分析的机车铸造牵引座焊后疲劳失效机制研究
Research on Fatigue Failure Mechanism of Locomotive Casting Traction Seat After Welding Based on Fracture Analysis
摘要
Abstract
Aiming at the problem of high crack rate in key positions of cast traction seats for railway locomo-tives during long-term service,a study was conducted on the post-weld fatigue failure mechanism at key posi-tions of cast traction seats based on fracture analysis.Firstly,a experimentally validated finite element model of the traction seat was established,and it was determined that there is a significant stress concentration area at 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 mi-croscopy(SEM)observation,metallographic examination,and energy dispersive spectroscopy(EDS)were per-formed on the fatigue crack failure area,indicating the presence of obvious welding repair marks and heat-treat-ed microstructure in the crack area.The research results indicate that the fatigue cracking failure of the traction seat is the result of the combined effect of stress concentration at the base arc and defects introduced by welding repair.It is important to focus on controlling the casting quality at the large arc of the base and avoid welding re-pairs.The research can provide theoretical guidance for the safe and efficient operation of railway freight and the maintenance and repair of parts.关键词
机车铸造牵引座/高周疲劳试验/断口分析/疲劳失效Key words
locomotive casting traction seat/high cycle fatigue test/fracture analysis/fatigue failure分类
交通工程引用本文复制引用
朱涛,齐红瑞,太万秋,张帆,王超,肖守讷..基于断口分析的机车铸造牵引座焊后疲劳失效机制研究[J].华东交通大学学报,2025,42(4):29-36,8.基金项目
四川省自然科学基金创新研究群体项目(2025NSFTD0014) （2025NSFTD0014）
国家重点研发计划(2022YFB4301201) （2022YFB4301201）
