Selective laser melting (SLM) is an additive manufacturing process, which allows for producing parts of very complex geometry. While SLM may produce the desired net-shape geometry, the surface conditions of as-built SLM parts are often insufficient. Also, the as-built state may yield undesired tensile stresses at the surface. Post processes such as magnetic field-assisted finishing (MAF) processes can yield the desired surface roughness and improve the residual stress state. However, in a part made by SLM, these processes will act on surfaces with various different orientations to the built direction, and, in particular, to the laser scanning direction. This paper analyzes the influence of laser scanning direction with respect to the surface to be finished by MAF using 316L steel disks produced with different orientations and scan strategies. The build plane of an as-printed disk has greater surface roughness and hardness but lower tensile residual stresses than the plane perpendicular to the build plane. These characteristics create difficulties in material removal and smoothing but do not impede MAF’s ability to increase hardness and impart compressive residual stresses to the surface scanned by the laser. The results indicate that material removal rate and hence optimal finishing time depend on the orientation of the surface with respect to the scanning direction, which should be accounted for in process planning.

选择性激光熔化（SLM）是一种增材制造工艺，可用于生产几何形状非常复杂的零件。尽管SLM可能会产生所需的最终形状，但已建成的SLM零件的表面条件通常不足。同样，建成状态可能会在表面产生不希望的拉伸应力。诸如磁场辅助精加工（MAF）工艺之类的后工艺可以产生所需的表面粗糙度并改善残余应力状态。但是，在由SLM制成的零件中，这些过程将作用于相对于构建方向（尤其是激光扫描方向）具有各种不同方向的表面上。本文使用不同取向和扫描策略生产的316L钢盘分析了激光扫描方向对MAF待加工表面的影响。与垂直于构建平面的平面相比，印刷后的磁盘的构建平面具有更大的表面粗糙度和硬度，但具有更低的拉伸残余应力。这些特性在材料去除和平滑方面造成困难，但不会妨碍MAF增加硬度并向由激光扫描的表面施加压缩残余应力的能力。结果表明，材料去除率以及因此最佳的精加工时间取决于表面相对于扫描方向的方向，这应在工艺计划中加以考虑。这些特性在材料去除和平滑方面造成困难，但不会妨碍MAF增加硬度并向由激光扫描的表面施加压缩残余应力的能力。结果表明，材料去除率以及因此最佳的精加工时间取决于表面相对于扫描方向的方向，这应在工艺计划中加以考虑。这些特性给材料去除和平滑带来了困难，但并不妨碍MAF增加硬度并向由激光扫描的表面施加压缩残余应力的能力。结果表明，材料去除率以及因此最佳的精加工时间取决于表面相对于扫描方向的方向，这应在工艺计划中加以考虑。