Additive Manufacturing of Metallic Materials: Case Studies in the Processing of Stainless Steel 316L and of Alloy Ti-6Al-4V by Laser Beam Melting

This powerpoint presentation was used as teaching material in a seminar given as part of the course “Compléments de fabrication mécanique et FAO” at Université catholique de Louvain. It outlines important current issues in the developments of additive technologies for the processing of metallic materials by discussing two case studies from researches carried out by the Metallic Materials Science Unit (ULg). In particular, two different metallic alloys, i.e. stainless steel 316L and Ti-6Al-4V, have been processed by laser beam melting under similar conditions, and their microstructures and mechanical behaviours have been compared in details. Under the investigated conditions, Ti-6Al-4V exhibits a more complex behaviour than stainless steel 316L with respect to the occurrence of microstructural and mechanical anisotropy. Moreover, Ti-6Al-4V appears more sensitive to the build-up of internal stresses when compared with stainless steel 316L, whereas stainless steel 316L appears more prone to the formation of “lack of melting” defects. This correlates nicely with the difference in thermal conductivity between the two materials. Thermal conductivity was also shown to increase strongly with increasing temperature.