The microstructures of the Fe-based alloy laser cladding layer were characterized by optical microscope, scanning electron microscope and X-ray diffractometer. The load-bearing performance was evaluated and compared with that of the U75V rail. 3D finite element modelling was performed using the ANSYS software. It is found that the phases of the coating are α-Fe, Fe-Cr, Ni-Cr-Fe and Fe₂B, Fe₃Si precipitates. The average microhardness of the coating can reach HV455.2, which is higher than that of the heat affected zone (HAZ) and the substrate. The coating can effectively reduce the wear and rolling contact fatigue of heavy-haul rail.

中文翻译：

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U75V钢轨激光熔覆铁基合金的动态承载性能

采用光学显微镜、扫描电镜和X射线衍射仪对Fe基合金激光熔覆层的微观结构进行了表征。对承载性能进行了评估，并与 U75V 导轨的承载性能进行了比较。使用 ANSYS 软件进行 3D 有限元建模。发现镀层的相为α-Fe、Fe-Cr、Ni-Cr-Fe和Fe ₂ B、Fe ₃ Si析出物。涂层的平均显微硬度可达HV455.2，高于热影响区（HAZ）和基体。该涂层可有效降低重载钢轨的磨损和滚动接触疲劳。