In selective laser melting (SLM) systems, a large portion of powder remains unconsolidated and therefore recycling powder could make SLM more economical. Currently, a lack of literature exists specifically targeted at studying the reusability of powder. Furthermore, the definition of powder reusability is complex since powder degradation depends on many factors. The goal of the current research is to investigate the effects of area fraction and part spacing on the degradation of 304L powder in SLM. An experimental study was conducted where various area fractions and part distances were chosen and powder characterization techniques for determination of particle size distributions, tap and apparent densities, and x-ray diffraction were employed to track evolving powder properties for the purpose of reuse. The results show that the recyclability of 304L powder depends on the utilization of the build area causing varying degrees of particle size coarsening and delta ferrite formation.
C. S. Kriewall et al., "Effects of Area Fraction and Part Spacing on Degradation of 304L Stainless Steel Powder in Selective Laser Melting," Proceedings of the 28th Annual International Solid Freeform Fabrication Symposium (2017, Austin, TX), pp. 277-288, University of Texas at Austin, Aug 2017.
28th Annual International Solid Freeform Fabrication Symposium -- An Additive Manufacturing Conference, SFF 2017 (2017: Aug. 7-9, Austin, TX)
Materials Science and Engineering
Mechanical and Aerospace Engineering
Intelligent Systems Center
Article - Conference proceedings
09 Aug 2017