Effect of preheat and layer thickness on selective laser melting (SLM) of magnesium

Abstract

Purpose– The purpose of this paper is to investigate the effect of preheat and layer thickness in selective laser melting (SLM) of magnesium using pulse mode. Magnesium has been considered as a new generation of implant materials which are bioactive and biodegradable for orthopaedic applications.Design/methodology/approach– To produce optimal single magnesium tracks to compare the effect of layer thickness and preheat, different laser parameters were investigated. The analysis was made based on digital and electronic microscope images and mechanical measurements.Findings– Improvements in the magnesium tracks due to preheating were successfully achieved. The analysis shows better bonding to the surface. The preheated tracks present an improvement in quality surface: smoother and flatter surfaces are discovered for the low layer thicknesses. When the thickness increases, the surface was disrupted and presented high surface roughness values. These were attributed to the Marangoni convection.Originality/value– This study continues valuing the fabrication of magnesium with SLM. It shows the improvements of preheat and effect of different layer thicknesses on the part properties.