为提高AZ31B镁合金表面的耐磨性，利用5 kW横流连续CO2激光器，配制了质量比为61的Al-Si/Al2O3-TiO2复合粉，在AZ31B镁合金表面进行了激光熔覆试验研究。通过光学显微镜（OM）、扫描电子显微镜（SEM）、X射线衍射（XRD）仪、能谱分析仪（EDS）分析了熔覆层的组织、界面结合及成分分布情况，并利用显微硬度仪、磨损试验机测试了熔覆层的表面性能。结果表明，激光熔覆复合涂层与基体达到了良好的冶金结合，结合界面清晰可见，XRD结果表明复合涂层由Mg17Al12、Al3Mg2、Mg2Si、Al2O3、TiO2 5种化合物组成；复合涂层最高硬度达245 HV0.05，比基体（50 HV0.05）提高了约4倍；由于陶瓷颗粒的镶嵌和镁铝金属间化合物的综合作用使得复合涂层的磨损性能也得到明显提高，磨损量比原始镁合金减少了81.4%。

To improve the wear resistance of AZ31B magnesium alloy, laser surface cladding with Al-Si and Al2O3-TiO2 mixture powders (in the mass fraction ratio of 61) is investigated by a CO2 laser. The microstructure, phase analyses and wear behavior of AZ31B modified is studied by optical microscopy (OM), scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), X-ray diffraction (XRD) and wear methods. The XRD pattern shows that the coating is composed of Mg17Al12, Al3Mg2, Mg2Si, Al2O3, TiO2, etc. The average microhardness of the surface layer is significantly improved to 245 HV0.05, as 4 times higher of that of the AZ31B substrate. The coating′s excellent wear resistance is due to the recombination of embedding of ceramic particles and intermetallic compounds. The worn mass of the composite coating decreases by 81.4% compared with that of the substrate.