Investigating the Effect of Laser Power and Scanning Strategy on Porosity in PBF-LB of 316L Stainless Steel

Abstract

This study aims to investigate the influence of laser power and scanning strategy on the formation of macro-scale pores in laser-based powder bed fusion of metals (PBFLB/M) for the manufacturing of 316L stainless steel. Samples were fabricated with varying laser powers and scanning strategies, and their porosity levels were analysed using optical microscopy and image analysis techniques. Volumetric energy density (VED) has been widely employed in previous studies as a comparative tool for integrating process parameters; however, its simplifications can obscure the influence of individual factors. In this study, laser power was found to have a significant effect on porosity formation, with an optimal VED value of 93 J/mm(3) minimizing defects. However, the impact of scanning strategy on porosity was inconclusive due to limited data. Future studies should focus on expanding the dataset to further assess scanning strategies and explore advanced methods to mitigate porosity-related defects, aiming to improve the reliability and performance of additively manufactured components.