Laser Powder Bed Fusion of WE43 in Hydrogen-argon-gas Atmosphere

Growing demand for individual and especially complex parts with emphasis on biomedical or lightweight applications enhances the importance of laser powder bed fusion. Magnesium alloys offer both biocompatibility and low density, but feature a very high melting point of oxide layers while the evaporation temperature of pure magnesium is much lower. This impedes adequate part quality and process reproducibility. To weaken this oxide layer and enhance processability, a 2 %-hydrogen-argon-gas atmosphere was investigated. A machine system was modified to the use of the novel inert gas to determine the influence of gas atmosphere on hollow cuboids and solid cubes. While processing a 20.3 % decrease in structure width and 20.6 % reduction in standard deviation of the cuboids was determined. There was no significate influence on relative density of solid cubes although eight of the ten highest density specimen were fabricated with the hydrogen addition.