采用选区激光熔化技术（SLM）在不同扫描速度（700~1 200 mm·s^-1）下成形316L不锈钢试样，研究了扫描速度对微观形貌和力学性能的影响。结果表明：随着扫描速度的增加，试样的表面粗糙度增大，内部空隙增多；试样的抗拉强度、断后伸长率和硬度先呈缓慢增加趋势，当扫描速度大于1 000 mm·s^-1时呈快速降低趋势，屈服强度一直呈降低趋势。随着扫描速度增加，试样的冲击吸收能量先保持稳定后下降，冲击断口附近的孔洞和裂纹逐渐增多，冲击断裂形式由韧脆性断裂变为脆性断裂；当扫描速度在700~800 mm·s^-1时，试样的冲击韧性最优，冲击吸收能量在58.6~60.0 J。

316L stainless steel specimens were prepared by selective laser melting (SLM) at different scanning speeds (700-1 200 mm·s^-1). The influence of the scanning speed on the micromorphology and mechanical properties was studied. The results show that with the increase of the scanning speed, the surface roughness and the internal voids of the specimen increased in number; the tensile strength, percentage elongation after fracture, and hardness of the specimen first slowly increased, and then rapidly decreased when the scanning speed was greater than 1 000 mm·s^-1, while the yield strength showed a decreasing trend. With increasing scanning speed, the impact absorption energy of the specimen first remained stable and then decreased, the number of holes and cracks near the impact fracture gradually increased, and the impact fracture form changed from ductile-brittle fracture to brittle fracture. When the scanning speed was 700-800 mm·s^-1, the impact toughness of the specimen was the best, whose impact absorption energy was 58.6-60.0 J.