利用6 kW横流CO2激光器在H13钢基材表面原位合成了以TiC颗粒为增强相的复合熔覆层。借助X射线衍射(XRD)和能谱仪(EDS)分析了涂层的物相组成，结合光学显微镜(OM)和扫描电子显微镜(SEM)观察了涂层的微观组织，运用显微硬度仪和摩擦磨损试验机测试了涂层的硬度和摩擦磨损性能。结果表明，当预置层中Ti与Cr3C2物质的量比为2.441时，熔覆层的主要物相为碳化物TiC、Cr7C3和Fe-Cr固溶体。随着预置层中Ti含量的减少，即当预置层中Ti与Cr3C2物质的量比为21时，熔覆层中Cr7C3相增多，而当预置层中Ti与Cr3C2物质的量比为22.33时，熔覆层中则出现 (Cr,Fe)7C3相。SEM和EDS分析显示，TiC增强相随激光功率密度的增大由球状向薄层状转变。当预置层中Ti与Cr3C2物质的量比为22.33，激光功率密度为24.38 kW·cm-2时，涂层表面宏观质量良好，无气孔裂纹缺陷，涂层截面平均显微硬度达到931.9 HV0.2，约为基材的2.21倍，最低磨损失重仅为基材的27.2 %。

In-situ TiC particle reinforce composite coating is synthesized on H13 steel surface by laser cladding technique. The phase composition, microstructure, friction and wear behavior and Vickers hardness of composite coating are analyzed using X-ray diffraction (XRD), energy dispersive spectrometer (EDS), optical microscopy (OM), scanning electron microscopy (SEM), wear testing machine and Vickers hardness gage. The results show that the laser cladding composite coating is mainly composed of TiC, Cr7C3 and Fe-Cr phases under the molar ratio of Ti to Cr3C2 of 2.441 condition. The content of Cr7C3 phase in coating increases under the molar ratio Ti to Cr3C2 of 21 condition, while (Cr, Fe)7C3 phase is found under the molar ratio Ti to Cr3C2 of 22.33 condition. SEM and EDS analysis indicate that the microstructure of TiC phase gradually changes from ball shape to lamellar with the increasing of laser power density. The cladding coating surface macro morphology is good and no pores or cracks under the molar ratio Ti to Cr3C2 of 22.33 and the laser power density 24.38 kW·cm-2 condition. The highest average Vickers hardness of the laser cladding composite coating is 931.9 HV0.2, which is about 2.21 times higher than that of the H13 steel substrate. The lowest wear weight loss of the composite coating is only 27.2 % of the substrate.