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

International Solid Freeform Fabrication Symposium 2023
14. - 16. August
Austin, TX, USA
2023
Type: Konferenzbeitrag
Abstract
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.