高速与重载铁路的疲劳磨损对比研究
A Comparative Investigation between Rolling Contact Fatigue and Wear of High-speed and Heavy-haul Railway
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摘要: 滚动接触疲劳和磨损是铁路钢轨损伤的主要问题.研究根据赫兹接触理论在JD-1型轮轨模拟试验机上通过改变车速和轴重来模拟高速和重载铁路的滚动接触,并用光镜和扫描电镜研究磨损表面,分析高速和重载条件下钢轨的磨损与疲劳机理.结果表明:随车速增加,钢轨磨损量减小,但出现大量斜裂纹,接触疲劳加剧.而随着轴重增加,塑性变形明显,磨损量迅速增加,但由于部分刚萌生的微裂纹被磨去,疲劳损伤较为轻微.Abstract: Rolling contact fatigue (RCF) and wear are inevitable problems for the infrastructure of modern railway. The rolling tests of railway rail were performed using a JD-1 wheel/rail simulation facility without any lubricant. The failure behavior of rail rollers with different axle load and speed was investigated in detail by examining wear volume and wear scar using optical microscopy and scanning electronic microscopy. The results indicate that the crack propagation was more significant and fatigue damage was more severe at high speed. The wear volume of rail roller became larger on heavy haul railway. The results show that there was a mutual competitive relationship between wear and surface fatigue crack. A high wear rate can reduce rolling contact fatigue damage by removing surface cracks.