Further studies in selective laser melting of stainless and tool steel powders

Previous reported work on the selective laser melting of a H13 tool steel powder bed surface has shown that there is a scan speed range in which the layer mass increases/fluctuates with increasing speed. This paper expands the investigation towards M2 tool steel and 316L stainless steel powders to identify if they reveal similar behaviours. Wide ranges of scan spacings and scan speeds have been examined, at selected laser powers. Furthermore, the masses of the layers have been compared with those predicted from an existing finite element thermal model. It has been found that at a constant laser power, the variation of mass with scan speed is much less than might be expected from a constant assumed absorptivity into a powder bed.