Selective Laser Sintering versus Multi Jet Fusion: A Comprehensive Comparison Study Based on the Properties of Glass Beads‐Reinforced Polyamide 12

Selective laser sintering (SLS) and multi jet fusion (MJF) are the most widespread powder bed fusion additive manufacturing techniques for fabricating polymeric parts since they offer great design flexibility, productivity, and geometrical accuracy. However, these technologies differ in the thermal energy source used to melt the powders as well as the innovative use of printing agents featured in the latter one to promote material consolidation and to avoid thermal bleeding at the part contours. The use of a single powder made of glass beads‐reinforced polyamide 12 (PA12/GB) for the fabrication of MJF and SLS samples makes possible a systematic comparison of the printed parts properties. A thoughtful analysis of the microstructure and mechanical properties of the samples reveals differences and peculiarities between the two technologies. SLS exhibits lower porosity and higher mechanical performances when the parts are printed along the build plane thanks to the powerful heating ensured by the laser. In contrast, MJF samples show higher mechanical isotropy with great flexural and tensile behavior for vertically oriented parts. The role of glass beads in the material behavior is defined by their mechanical properties, meaning higher rigidity and lower strength compared to neat PA12, and fracture mechanism. The aim of this study is the comparison between selective laser sintering and multi jet fusion by processing the same glass beads‐reinforced PA12 powders. The properties of the feedstocks guarantee high processability and low porosity in both cases. However, differences in terms of microstructure, mechanical isotropy, and fracture mechanism of the printed samples are observed.