采用选区激光熔化(SLM)技术成型钴铬合金, 运用正交实验法研究了激光功率P、扫描速度v、铺粉厚度h和扫描间距d对多层成型件致密度、上表面粗糙度和侧面粗糙度的影响规律。实验结果表明, 铺粉厚度是影响SLM成型件致密度大小的最重要因素, 而激光功率是影响成型件上表面和侧面粗糙度的最重要因素。获取了优化的工艺参数为P＝170 W, v＝500 mm/s, h＝0.03 mm, d＝0.08 mm, 该工艺参数下成型件的致密度最高达97.05%, 上表面粗糙度Ra最低为20.3 μm, 侧面粗糙度Ra为15.5 μm。致密度和表面粗糙度之间存在相互影响关系, 表面粗糙度的累积效应会导致成型件致密度降低。

Selective laser melting was used to form Co-Cr alloy. The orthogonal experiment was used to study the influence laws of laser power P, scanning speed v, powder layer thickness h and scanning distance d on the density, surface roughness and side roughness were analyzed. The experimental results showed that the powder layer thickness was the most important factor affecting the density of the molded parts, and the laser power was the most important factor affecting the roughness of the top surface and side of the molded part. The optimized process parameters were P＝170 W, v＝500 mm/s, h＝0.03 mm, d＝0.08 mm. The highest density of the molded part was up to 97.05%, the lowest top surface roughness was 20.3 μm, the side surface roughness was 15.5 μm. There is an interaction relationship between density and surface roughness, and the cumulative effect of surface roughness can lead to a decrease in the density of the molded part.