目的 提升低温钢的摩擦磨损性能，为极地特殊船板的焊补和延寿技术提供试验依据。方法 利用等离子转移弧技术，在低温钢E32表面堆焊制备3组球形不同碳化钨含量的钴基涂层，比较该改性涂层和E32钢在低温条件下(–20 ℃)的摩擦磨损性能。通过X射线衍射仪、扫描电子显微镜、能谱分析仪、3D光学轮廓仪等研究手段，分析碳化钨含量对堆焊层耐磨损性能和显微组织的影响规律，并揭示其耐磨损机理。结果 在载荷为50 N、滑动速度为20 mm/s条件下，经2 h干滑动摩擦磨损后，3组涂层较低温钢E32的摩擦系数和体积磨损率均下降，磨痕的宽度和深度均变小。富含WC、W2C增强相以及Cr23C6、Cr7C3、Co6W6C和Fe6W6C等碳化物硬质相的涂层，显著提升了E32钢的硬度和低温耐磨性。涂层的低温耐磨性能随着碳化钨含量的增大而提高，未添加碳化钨的涂层的主要磨损机理为磨粒磨损和粘着磨损，当碳化钨的质量分数为30%和60%时，主要磨损机理为三体磨粒磨损。结论 通过在E32钢表面进行等离子转移弧堆焊，得到了结构致密、高硬度和抗低温耐磨性的球形碳化钨增强钴基表面改性涂层，在一定程度上提升了低温钢的服役寿命。

Enhancement of friction and wear performance of low temperature steel by plasma transfer arc welding (PTAW) technology to provide a test basis for welding and life extension technology for polar special ship plates. Three sets of Co-based coatings with spherical tungsten carbide content were prepared by overlay welding on the surface of low-temperature steel E32 using plasma transfer arc technology, and the frictional and wear performance of this modified coating and E32 steel at low temperature conditions (–20 ℃) was compared. By means of X-ray diffractometer (XRD), scanning electron microscope (SEM), energy disperse spectroscopy (EDS) and 3D optical profilometer, the influence law of tungsten carbide content on the wear resistance and microstructure of the overlay layer was analyzed, and the wear resistance mechanism was revealed. After 2 h dry sliding friction wear with a load of 50 N and a sliding speed of 20 mm/s, the friction coefficient and volume wear rate of the three sets of coatings decreased compared to the low temperature steel E32, and the width and depth of the wear marks became smaller. Coatings rich in WC, W2C reinforced phases and carbide hard phases such as Cr23C6, Cr7C3, Co6W6C and Fe6W6C significantly improve the hardness and low temperature wear resistance of E32 steel. The low temperature wear resistance of the coating increases with the increase of tungsten carbide content. Adhesive wear and abrasive wear were predominant wear mechanism of the coating when the coating without adding tungsten carbide. When the content of tungsten carbide was 30% and 60%, three-body abrasion was the main wear mechanism. Through PTAW on the surface of E32 steel, the spherical tungsten carbide reinforced Co-based modified coatings with dense structure, high hardness and excellent low-temperature wear resistance were obtained, which can improve the service life of low-temperature steel to some extent.