目的 提高钛合金表面的耐磨性能。方法 在TiB2:TiC=1:3的粉末配比下，添加不同质量分数Y2O3稀土氧化物，制备成膏状混合粉末。采用5 kW横流CO2激光器，在TC4钛合金表面激光熔覆掺Y2O3的TiB2和TiC粉末，制备耐磨性复合涂层。通过扫描电子显微镜（SEM）、X射线能谱仪（EDS）、X射线衍射仪（XRD）对激光熔覆层的微观形貌和组织成分进行了分析；用显微维氏硬度计对熔覆层的显微硬度进行了测量；用万能摩擦磨损试验机对熔覆层的耐磨性能进行了测试。结果 添加4%Y2O3后，熔覆层中部组织明显细化，结合区由致密组织结构转变为晶须网状结构；熔覆层的最高显微硬度为1404.6HV0.2，是基体的3.7倍；熔覆层的磨损量减少了66.67%，且其摩擦系数有明显的降低。结论 添加4%Y2O3对TC4钛合金表面激光熔覆TiB/TiC复合熔覆层耐磨性能有显著的提高。

The work aims to improve wear resistance of TC4 titanium alloy. Pasty mixed powder was prepared at a proper ratio of TiB2:TiC (1:3) and adding Y2O3 rare earth oxide in different mass fractions. Wear resistant composite coating was prepared by laser cladding Y2O3-doped TiB2 and TiC powder on the surface of TC4 titanium alloy using 5 kW continuous wave CO2 laser. Microstructure and composition of the laser cladding layers were analyzed with scanning electron microscope (SEM), energy dispersive spectrometer (EDS) and X-ray diffractometer (XRD); microhardness of the laser cladding layer was measured with Vickers hardness tester; and wear resistance was tested with universal friction and wear tester. After 4% Y2O3 was added, grain size of the middle structure was greatly refined; microstructure of the bonding zone was transformed from compact structure to reticular whisker structure; maximum microhardness of the cladding layer was 1404.6HV0.2, 3.7 times as high as that of TC4 substrate; wear loss of the cladding layer decreased by 66.67%, and the friction coefficient decreased remarkably. Wear resistance of the laser cladded TiC/TiB composite cladding coating on the surface of TC4 titanium alloy can be improved significantly by adding 4% Y2O3.