采用激光熔覆技术在40Cr钢表面制备了Co基熔覆层。利用体式显微镜和显微硬度计,对熔覆层分别进行了宏观形貌观察和显微硬度测试。根据熔覆后零件的实际工作状况,有针对性地采取了滑动+滚动的摩擦方式对熔覆件进行干摩擦试验。结果表明,随着激光功率的增加,熔覆层参数(熔高、熔深、熔宽)逐渐增加;显微硬度则出现先升高而后降低的趋势;其磨损机理依次呈现氧化磨损-磨粒磨损-粘着磨损-疲劳磨损。研究发现提高零件硬度不等于提高了耐磨性。 The Co-based cladding layer was prepared on 40Cr steel by laser cladding. Using the microscope and the microhardness tester, the macroscopic morphology and the microhardness test of the cladding were carried out respectively. According to the actual working condition of the cladded parts, the friction and friction of the cladded parts were tested by the friction and slip method. The results show that with the increase of laser power, the cladding parameters (melting height, penetration depth and melting width) increase gradually and the microhardness firstly increases and then decreases. The wear mechanisms are oxidized and wear - Wear - Adhesive wear - Fatigue wear. The study found that increasing the hardness of the part did not mean improving the wear resistance.