Wear Property of U71MnK Rail Weld under Rolling Contact

The material wear and the evolution of the rail weld and base material in the process of rolling contact were investigated through the simulated experiments. The results show that there were significant differences between the weld and the non-weld before and after wear. Due to the differences in microstructure and mechanical properties,the hardness of the weld zone was lower than that of the non-weld zone. The friction coefficient,wear mass and wear rate of the weld zone were greater than that of the non-weld zone. Compared with the non-weld zone,the furrows and corrugations were prone to generate in the weld zone. Moreover,surface roughness increased. Spalling damage,cracks,plastic deformation aggravated and abrasion performance deteriorated in the weld zone. The previous microstructure both in the weld zone and the non-weld zone was refined by the previous wearing,which resulted in improved wear resistance . Thus,the abrasion damage reduced in the subsequent rolling contact.