为了提高收割机刀片的使用寿命, 采用激光熔覆工艺在45#钢表面制备了中锰铁基合金激光熔覆层。利用扫描电镜(SEM)、光学显微镜(OM)、X射线衍射仪(XRD)、显微硬度计和MLD-10型动载磨料磨损试验机分析了熔覆层的显微组织, 测试了涂层的显微硬度和冲击磨料磨损性能。结果表明: 涂层与基体形成冶金结合, 涂层无裂纹、气孔等缺陷。激光熔覆层的显微硬度为500～600 HV, 激光熔覆层与渗碳试样相比具有较高的抗冲击磨料磨损性能, 能够提高收割机刀片的使用寿命。

In order to improve the service life of the harvester blade, the medium manganese alloy laser cladding coating has been prepared on the surface of 45# steel by laser cladding. The microstructure, hardness, impact abrasive wear resistance of cladding layer were researched by scanning electron microscope, optical microscope, X-ray diffractometer, micro-hardness tester and MLD-10 type impact abrasive wear tester. The results show that there was a good metallurgical bond between coating and substrate and the coating was free of cracks and pores. The micro-hardness of laser cladding layer is 500～600 HV. Compared with the carburized sample, the laser cladding layer has higher impact abrasive wear resistance, and can improve the service life of the harvester blade.