Influence of powder production process and properties on material properties of Ti6Al4V manufactured by L-PBF

Abstract

Besides process parameters, powder properties such as grain size, morphology, and chemical composition have the highest impact on the material properties of parts produced by powder-based additive manufacturing. These properties are strongly influenced by the production process of the powder and its feedstock. In the scope of this work, the influence of three different powder producers of Ti6Al4V, on density, chemical composition, and mechanical properties of build samples, is investigated. Furthermore, the effects of the varying atomization process on morphology, particle size distribution, chemical composition, and oxide layers are studied. Particle size distribution and flowability seem to have a minor influence on the production process while density depends highly on the surface topology, sphericity, and nature of the oxide layer, which affect energy intake. Tensile properties are highly influenced by chemical composition, mainly dissolved oxygen, and polluting satellites, while notched bar impact strength is additionally influenced by the oxide layer and suspected TiO2 precipitations caused by it.