提出采用激光熔凝———稀土扩渗复合处理对钢表面改性的新方法。实验结果表明 ,该方法可以进一步改善渗稀土试样表层显微组织 ,使其晶粒得到明显细化 ,组织更加均匀、致密 ,渗入元素浓度梯度减小 ,耐腐蚀和抗磨损性能显著提高 ,可在工业上推广使用 A new method of modifying the surface of steel by laser melting-rare earth expansion and composite treatment is proposed. The experimental results show that the method can further improve the microstructure of the surface of the rare earth-infiltrated sample, so that the crystal grains are obviously refined, the structure is more uniform and dense, the concentration gradient of the infiltrated element is reduced, the corrosion resistance and abrasion resistance are significantly improved, In the industrial promotion and use