为研究工艺参数对激光选区熔化纯铜粉末成形件上表面粗糙度的影响, 采用正交实验对纯铜粉末进行了激光选区熔化成形研究。分析了铺粉厚度为0.05 mm时, 工艺参数对成形件上表面粗糙度的影响规律及影响机理, 确定了各工艺参数对上表面粗糙度影响的主次顺序为扫描间距＞扫描速度＞激光功率＞扫描路径, 得到最优的工艺参数组合为激光功率 380 W, 扫描速度 600 mm/s, 扫描间距 0.05 mm, 扫描方式选择正交形。结果表明: 在因素水平范围内, 成形件上表面粗糙度随激光功率的增大而减小, 随扫描速度、扫描间距的增大而增大, 采用正交形的扫描路径可得到相对低的表面粗糙度。体能量密度在180 J/mm3至200 J/mm3之间时, 上表面粗糙度最低。

In order to study the effect of process parameters on upper surface roughness of the selective laser melting copper powder forming parts, orthogonal experiment was adopted to carry out the research of the selective laser melting of pure copper powders. The influence rule of process parameters on the upper surface roughness of the forming parts and the influence mechanism were analyzed when the powder thickness was 0.05 mm. The primary and secondary order of the influence of each process parameter on the roughness of the upper surface was determined as hatch space＞scanning speed＞laser power＞scanning path. The optimal combination of process parameters was laser power of 380 W, scan speed of 600 mm/s, hatch space of 0.05 mm and scanning path is orthogonal. The results show that the upper surface roughness of the forming parts decreases with the increase of laser power, increases with the increase of scanning speed and hatch space. The surface roughness of the formed parts is relatively low, when the scanning path is orthogonal. When the volume energy density is between 180 J/mm3 and 200 J/mm3, the roughness of the upper surface is the lowest.