| Abstract Scope |
The low density and high biocompatibility of Mg-based materials make them suitable for lightweight structural and biomedical applications. In this study, selective laser melting (SLM), an emerging additive manufacturing process, was used to process pure Mg under various laser energy densities (η). The densification behavior, microstructure evolution, and microhardness were evaluated. Both the peak temperature gradients within the molten pool and the molten pool dimensions increased with increasing η, and an opposite trend was observed for the cooling rate. Low η generated low operating temperature and short liquid lifetime, resulting in poor wettability and large amount of porosity chain and balling phenomena. However, the increase in η generated melt pool instability, which resulted in extensive evaporation, cracks, and porosity, and was accompanied by an increase in the grain size due to the lower cooling rate. |