为研究激光功率对锡基巴氏合金熔覆层组织和性能的影响, 利用800 W、1 000 W、1 200 W激光功率在20钢表面制备锡基巴氏合金熔覆层。利用金相显微镜(OW)、扫描电子显微镜(SEM)、能谱仪(EDS)、X射线衍射仪(XRD)、摩擦磨损试验机分别对熔覆层的组织形貌、结合区形貌、摩擦学性能进行研究。结果表明, 随着激光功率的增大, 熔池的温度升高, 冷却速率降低, 硬质点颗粒SnSb的颗粒粒径随激光功率的升高逐渐增大。当激光功率较低时, SnSb颗粒尺寸较小, 分布均匀。随着激光功率的升高, SnSb相尺寸增加, 数量减少, 降低了熔覆层的硬度和耐磨性。当激光功率为800 W时, 熔覆层的显微硬度最大, 为35.7 HV, 平均摩擦因数为0.257, 磨损机制为磨粒磨损和表面疲劳磨损。

In order to study the effect of laser power on the microstructure and properties of tin-based Babbitt cladding layers, 800 W, 1 000 W and 1 200 W laser powers were used to prepare tin-based babbitt cladding layers on the surface of 20 steel. Phase constituents, microstructure, microhardness, and wear property of the Babbitt coatings with different laser power were investigated using XRD, SEM, microhardness tester, and friction-wear tester, respectively. The results showed that with the increase of laser power, the temperature of the molten pool increases, the cooling rate decreases, and the particle size of the SnSb hard spot particles increases gradually with the increase of laser power. The size of SnSb phase is smaller when the laser power is low, and the distribution is uniform. With the increase of laser power, the size and number of SnSb phase increases, and the hardness and wear resistance of the cladding layer also decrease. The average microhardness of the Babbitt alloy coatings of 800 W laser power is about 35.7 HV, the average friction coefficient is 0.257, and the wear mechanism are abrasive wear and surface fatigue wear.