Changes in Powder Surface Chemistry During Reuse of 316L in Powder Bed Fusion - Laser Beam

Paper in proceeding, 2024

Powder degradation during additive manufacturing poses a significant challenge for achieving optimal part quality as well as maximal powder feedstock utilization and hence economy and sustainability of the process. Stainless steel 316L is a widely utilized material in powder bed fusion - laser beam (PBF-LB) due to its excellent processability, good corrosion resistance and mechanical properties of the PBF-LB processed components. This study investigates the influence of 316L powder properties and powder reuse on the powder surface oxide chemistry and hence processability by PBF-LB. Changes in powder surface chemistry were studied by HR SEM and X-ray Photoelectron Spectroscopy in virgin and reused state. Results indicate that there is evident degradation in powder properties during powder re-use with increase in oxygen content in the powder, connected to increase in thickness of iron-base surface oxide layer as well as fraction of Cr-rich particulate oxide phases.