Influence of the Oxygen Content of Ti6Al4V Powder on Mechanical Properties of Additively Manufactured Components Using Laser-based Powder Bed Fusion

Ti6Al4V is the most commonly used titanium alloy in Laser-Based Powder Bed Fusion (LPBF) and is of interest for many applications. This applies in particular to the aerospace and medical technology sectors, where high demands are placed on part properties. The mechanical properties of Ti6Al4V are partly influenced by the oxygen content, which is therefore limited by specifications, e.g. for surgical implants. This raises the question for users to what extent the oxygen content increases when processed in LPBF and how the mechanical properties decrease when the powder is near the oxygen limits. In this paper, thus, three powders with an oxygen content of approx. 1700, 2100 and 2400 ppm are compared with regard to their particle size distribution, flow behavior and oxygen/nitrogen content. The resulting test specimens are then examined by means of microstructural examinations and tensile tests, which show the extent of embrittlement and oxygen increase of powders and samples.