目的 提高45#钢的使用性能和耐蚀性。方法 以316L不锈钢粉末为熔覆材料，在45钢退火基体表面制备不锈钢熔覆层，采用CCD中心组合设计，利用金相法检测熔覆层的几何形貌参数，利用光学显微镜（OM）和扫描电镜（SEM）分析熔覆层的显微组织，采用显微硬度计和磨损试验机测试熔覆层的显微硬度和磨损性能，利用电位极化曲线测试熔覆层的耐腐蚀性能。结果 当激光功率为600 W，扫描速度为22.5 mm/s，送粉速率为0.18 r/min时，熔覆层与基体呈良好的冶金结合。熔覆层的硬度在461.3~559.8HV，是基材硬度的2倍左右；磨损量为0.0146 g，是基材的0.1倍；摩擦系数较为稳定，保持在0.5左右，是基材的0.3倍左右；自腐蚀电流密度为3.274×10?7 A/cm2，是基材的0.7倍左右。结论 在45钢表面激光熔覆316L不锈钢涂层后，可有效提高其耐磨性和耐蚀性。

The work aims to improve usability and corrosion resistance of 45 steel. With 316L stainless steel powder as cladding material, stainless steel cladding layer was prepared on the surface of annealed 45 steel. CCD center combination design was adopted. Geometrical morphology parameters of the cladding layer was detected in metallographic method. Microstructure of the cladding layer was analyzed with optical microscopy (OM) and scanning electron microscopy (SEM). Microhardness and wear resistance of the cladding layer were measured with microhardness tester and wear tester. Corrosion resistance of the cladding layer was tested based upon polarization curve. The cladding layer exhibited metallurgical bonding to the substrate provided with laser power of 600 W, scanning speed of 22.5 mm/s, powder feeding rate of 0.18 r/min. Hardness of the cladding layer was 461.3~559.8HV, about 2 times that of the substrate; abrasion loss of the cladding layer was 0.0146 g, 0.1 times that of the substrate; friction coefficient was relatively stable and kept at 0.5, about 0.3 times that of the substrate self-corrosion current density was 3.274×10?7 A/cm2, 0.7 times that of the substrate. Laser cladding of 316L stainless steel coatings on annealed 45 steel can effectively improve wear resistance and corrosion resistance of the coatings.