为了提高低碳钢表面的耐磨性能，采用CO2激光堆焊系统，将Co基合金与WC混合粉末(WC的质量分数为0~0.47)用单道堆焊于低碳钢表面。利用X射线衍射仪、能谱分析仪、扫描电子显微镜、激光显微镜、维氏硬度计和耐磨试验机对单道堆焊层的相结构、显微组织、维氏硬度、耐磨性和裂纹敏感性进行了比较分析。结果表明，这种堆焊方法的堆焊层均为亚共晶组织，且未分解WC弥散分散在Co基合金的基体上; 堆焊层的维氏硬度均随WC含量的增加而增加。该方法具有较低的裂纹敏感性。

In order to improve the wear resistance of the clad layer, the powder mixture of stellite-6 and tungsten carbide (WC) in the range of 0~0.47 mass fraction of WC was deposited on mild steel plates by CO2 laser cladding system. The phase constitution, microstructure, hardness and wear resistance of the clad layer were studied with an X-ray diffractometer, energy dispersive spectroscopy, scanning electron microscope, laser microscope, Vickers hardness tester and wear tester. According to the analyzed results, the microstructure of the clad layer consists of hypoeutectic structure and undissolved tungsten carbides dispersed in the matrix of the Co-based alloy. The Vickers hardness increases with the increase of WC weight fraction. On the other hand, the crack sensitivity of the laser clad layer is low.