レーザ溶融式金属3DプリンタによるSUS630鋼造形物の表面性状に及ぼすプロセスパラメータの影響

抄録

Recently, selective laser melting (SLM) has been attracting attentions in manufacturing industry due to the advantage of fabricating complex geometries. However, there are several issues when SLM is applied to mechanical components in practical use, and the one of them is roughness control of SLM objects. In order to use SLM objects as mechanical components, it is necessary to clarify the influence of the process parameters on the surface roughness. In this study, precipitation hardening stainless steel (SUS630) specimens were fabricated under different combinations of laser irradiation parameters (laser power P, scan speed S and scan pitch D) and surface roughness Sa was measured by a 3D shape measuring spectroscopy. The effects of laser irradiation parameters on surface roughness were investigated by defining energy density E (= P/S) and scan pitch. As a result, it was found that the effects of energy density on surface roughness were dramatically changed under different conditions of scan pitch. The discontinuous molten traces and spatter particles were observed at the specific laser irradiation conditions using scanning electron microscope, which was considered to contribute the increment of surface roughness.