N. Emminghaus
R. Bernhard
J. Hermsdorf
L. Overmeyer
S. Kaierle

Influence of Silane-doped Argon Processing Atmosphere on Powder Recycling and Part Properties in L PBF of Ti-6Al-4V

Proceedings of the 34th Annual International Solid Freeform Fabrication Symposium - An Additive Manufacturing Conference
Type: Zeitschriftenaufsatz (reviewed)
In the additive manufacturing of metal powders, the residual oxygen in the processing atmosphere plays a crucial role, especially in highly reactive materials like titanium alloys. Besides oxidation of the built parts, it leads to oxygen pick-up into the unmolten powder. Since oxidized particles cannot be removed during recycling, the powder properties deteriorate after multiple uses. In this work, Ti-6Al-4V powder was processed under conventional argon atmosphere (residual oxygen content 0.01 vol\%) as well as silane-doped argon atmosphere ( 0.001 vol\% silane in argon). The silane-doping leads to a residual oxygen content of 10-20 vol\%. The powder was sieved and used 5 times for each atmosphere. The powder properties morphology, chemical composition and flowability were analyzed for virgin as well as reused powder. Furthermore, the roughness and relative density of the built parts were evaluated. It was hypothesized that oxygen-free production improves recyclability and thus resource efficiency.