17-4PH不锈钢应用十分广泛。采用激光选区熔化成形(Selective Laser Melting, SLM)技术可以无需磨具直接制备形状十分复杂的高性能金属零件。系统地研究了工艺参数对SLM成形17-4PH不锈钢的相对密度、尺寸精度和表面粗糙度的影响。结果表明: 扫描速度对以上参数的影响很大。随着扫描速度的增加, 相对密度先增加后减少, 尺寸偏差减少。随激光功率增加和层厚减小, 其相对密度和尺寸偏差均增大, 扫描间距的影响不明显。当扫描间距较小时, 随扫描速度增加, 表面粗糙度先增加后减小; 当扫描间距较大时, 随扫描速度增加, 表面粗糙度先减小后趋于稳定。优化的工艺参数下, Ra可以小于10 mm。

17-4PH stainless steel is widely applied in industrial application. Selective laser melting is a technology which can fabricate metal powder with high accuracy and performance. The investigation of the process parameters on the relative density, dimensional accuracy and surface roughness of SLM 17-4PH has been performed in this paper. The results show that the scanning velocity has the significant effect. As the scanning velocity increases, the relative density increases first and then decreases, the dimensional deviation decreases. As the laser power increases and layer thickness decreases, the relative density and dimensional deviation all increase. The effect of scanning spacing is weaker as comparing with the laser power and scanning velocity. As the scanning velocity increases, the surface roughness increases first and then decreases when the scanning velocity is small, the surface roughness increases first and then tends stable when the scanning spacing is large. 10 mm Ra can be achieved when the process parameters are optimal.