稀土对钢轨钢接触疲劳的影响

Influences of Rare Earths on Contact Fatigue of Rail Steel

利用接触疲劳磨损试验机模拟钢轨／车轮接触疲劳作用，研究了钢轨钢接触疲劳表面区剖面的形貌、显微结构和硬度。结果表明，稀土可延缓钢轨钢表面疲劳裂纹的萌生和扩展、推迟表面剥离、减小裂纹贯穿角和裂纹稳定贯穿深度、缩小塑性变形范围和改善表面加工硬化效果。

The contact fatigue of rail/wheel has been investigated using contact fatigue wear tester, and the microstructure and the microhardness in the fatigue profiles analyzed by scanning electron microscope and vickers hardness separately. The results show that rare earths are able to delay the initiation and propagation of fatigue crack, postpone surface shelling or spalling, reduce crack propagation angle, crack propagation depth and plastic deformation area, as well as improve work hardening.