目的 提高模切刀具刃口层硬度和耐磨性，使刃口层内部组织无缺陷。方法 以Ni45A-TiC-CeO2为熔覆材料，采用激光熔覆技术在AISI 1045钢表面制备不同含量稀土氧化物复合涂层。通过测试，分别研究不同含量CeO2(质量分数0%~5%)对熔覆层物相组成、显微组织、显微硬度和耐磨性能的影响规律。结果 添加CeO2后，熔覆层的物相主要包括TiC、Ni3Fe、Cr7C3、Cr23C6等，少量CeO2的加入未改变熔覆层内主要相的生成，在CeO2的质量分数为5%的条件下，在熔覆层中观测到Ce2O3相。当CeO2的质量分数为2%时，Ni45A-TiC-CeO2复合涂层表面无渣、无裂纹、润湿角较小、宏观形貌最好，从表面到与基体结合处涂层的显微组织无枝晶，组织得到明显细化，TiC形貌细化，且分布较均匀;平均显微硬度最高，为1 388.6HV，是未添加CeO2刃口层的1.151倍;平均摩擦因数和平均磨损体积最小，平均磨损体积为0.259×10^?3 mm³，相较于未添加CeO2的熔覆层，降低了47.358%，涂层的耐磨性能最好。结论 添加适量CeO2有助于改善涂层的宏观形貌，细化微观组织，提高涂层的显微硬度和耐磨性能。

The tool edge layer needs to have high hardness and wear resistance while the internal organization of the edge is required to be free of defects such as pores and cracks. However, due to the rapid heating and cooling rates in the laser cladding process, there are large thermal and phase change stresses in the cladding layer, and there are differences in physical and chemical properties between the enhanced phase and the base material, which can lead to defects such as coarse grains, pores and cracks in the cladding layer, thus the application of laser cladding technology in tool edge manufacturing is severely limited.