Abstract:Aiming at the remanufacturing difficulties of U71Mn track surface wear, low surface wear resistance and easy porosity defects caused by laser remanufacturing, the technology and method of preparing FeCrNiB coating on track surface by pulse laser cladding were proposed and verified. The results show that the top of the cladding layer is mainly distributed with fine and dense equiaaxial crystals, and there are more dendrites in the middle of the cladding layer. The dendrite grains have primary and secondary crystal arms, and the lower part of the cladding layer presents a cellular crystal structure, which is roughly perpendicular to the interface.The existence of Cr7C3 hard phase and nano-sized granular and flake pearlite structure in the cladding layer makes the cladding layer have high hardness and wear resistance, and the average hardness of the cladding layer increases from 310 HV0.2 to 750HV0.2.Under the same friction and wear conditions, the wear resistance of the cladding layer increases by 5 times.The tensile strength of butt sample is slightly less than that of matrix, but it can still meet the requirements of rail.