Influence of a Hydrogen Addition to the Inert Gas and Subsequent Heat Treatments on the Microstructure and Mechanical Properties of Magnesium WE43 Fabricated by PBF‐LB/M

Additive manufacturing of magnesium alloys shows great potential for producing patient‐specific resorbable implants or lightweight parts. However, due to the reactive behavior, especially in the laser‐based powder bed fusion (PBF‐LB) fabrication process, the processing window to manufacture almost pore‐free parts is narrow compared to other materials such as titanium or steel. This article investigates optimal processing conditions for the PBF‐LB/M of WE43. To reduce the reactivity of the magnesium melt by limiting the interaction with remaining oxygen, a 3 vol% hydrogen admixture to the argon inert gas is investigated. Furthermore, long‐duration heat treatments are investigated in the range of 250–350 °C for 48 h. This study evaluates the impact of both methods on mechanical properties and microstructure. Although hydrogen seems to have no significant influence on the relative density, the microstructure, and the phase composition, it can slightly increase the tensile strength and elongation at break in the as‐built state. A heat treatment of 250 °C can increase the elongation at the break without impeding the tensile strength.