激光熔凝316L不锈钢的摩擦学性能研究

Study on Tribological Properties of Laser Surface Melting 316L Stainless Steel

采用光纤激光器对316L不锈钢表面进行熔凝处理,研究了熔凝层微观组织演变及其摩擦学性能。结果表明:通过激光熔凝可在316L不锈钢表面获得冶金质量良好、无孔隙裂纹、厚度为500μm的熔凝层。与原始试样相比,激光熔凝处理使其表层从顶部至底部依次形成等轴晶、树枝晶与柱状晶的梯度细化组织,显微硬度提高约73.9%,摩擦因数降低约37.8%,磨损量降低约38.5%,磨损机制从磨粒磨损与黏着磨损转为轻微的磨粒磨损,表明其耐磨损性能经激光熔凝处理后得到明显提升。

The surface of 316Lstainless steel was melted by fiber laser.The effect of laser surface melting on the microstructure and wear resistance of 316Lstainless steel was studied.Results show that a 500μm thick layer with good metallurgical quality and free crack can be obtained on the surface of 316Lstainless steel by laser surface melting.Compared with the original sample,the gradient refinement structure of equiaxed crystal,dendrite and columnar crystal is formed in the surface layer from top to bottom,the microhardness is increased by 73.9%,the friction coefficient is reduced by 37.8%,and the wear loss is reduced by 38.5%.The wear mechanism changes from abrasive wear and adhesive wear to slight abrasive wear,which indicates that the wear resistance of the substrate is significantly improved after laser surface melting treatment.