Experimental investigation between rolling contact fatigue and wear of high-speed and heavy-haul railway and selection of rail material

摘要

The rolling tests of railway rail were performed using a JD-1 wheel/rail simulation facility on basis of Hertz Contact Theory. The wear and fatigue mechanism of rail rollers at different speed and axle load was investigated in detail by examining wear volume and wear scar using optical microscopy (OM) and scanning electronic microscopy (SEM). The results indicate that with speed increasing, the wear volume of rail is reduced, as well as many oblique cracks initiate and contact fatigue becomes severer; with axle load increasing, the plastic deformation becomes severer, increasing of wear volume and fatigue failure become slight due to removing of micro-cracks partly. For the rail material with a higher hardness, the wear volume is less and plastic deformation layer is thinner after the rolling test. However, its crack propagation is more significant and the fatigue damage is severer with better wear resistance. Meanwhile, for the rail material with a lower hardness, the wear volume is larger and the plastic deformation layer is thicker. In addition, high wear rate reduces the rolling contact fatigue damage by constantly removing surface cracks. The analysis shows that U75V quenched rail with better wear resistance is suitable for heavy haul railway and U71Mn hot rolled rail with better fatigue resistance is more suitable for the high-speed railway.