中文摘要：

采用CO2激光熔覆工艺在304不锈钢表面制备含Ti（C,N）增强相的铁基熔覆层。利用光学显微镜、X射线衍射仪、扫描电镜、维氏显微硬度计和电化学工作站对熔覆层的组织和性能进行表征分析。结果表明熔覆层呈典型的树枝晶形貌组织,与基体形成了良好的冶金结合。钛铁粉末与石墨、氮气在激光熔覆过程中发生了原位反应,生成了Ti（C,N）增强相。熔覆层主要由γ-Fe、α-Fe、Ti（C0.3N0.7）、Fe-N等物相组成。熔覆层的平均硬度值为450HV0.2,是基体硬度（240HV0.2）的近2倍。抗电化学腐蚀性能是304不锈钢基材的1.43倍。

英文摘要：

Fe-based composite layer with Ti （C, N） strengthening particles was prepared on 304 stainless steel surface by CO2 laser cladding technology. Microstructure and properties of the cladding layer were studied by optical microscopy, X-ray diffractometer, scan electron microscopy, micro-hardness tester and electrochemical workstation. The results show that the cladding layer is a typical dendritic structure and it is well bonded with the substrate. Ti （C, N） strengthening particles are formed by in-situ reaction of titanium iron powder with graphite and nitrogen in the process of laser cladding. The cladding layer is composed of γ-Fe, α-Fe, Ti （C0.3N0.7） and Fe-N phases. The average micro-hardness of the cladding layer is 450 HV0.2, which is nearly twice than that of substrate （240 HV0.2）. The electrochemical corrosion resistance of the cladding layer is 1.43 times than that of the substrate.