Investigating the impact of a selective laser melting process on Ti6Al4V alloy hybrid powders with spherical and irregular shapes

A hybrid powder of Ti6Al4V, which consists of 50 wt% plasma atomised (PA) spherical and 50 wt% hydride-dehydride (HDH) irregular-shaped powder with a flowability of 36.5 s, is projected as the raw materials in this research. In addition, Ti6Al4V (Gr.23) plasma atomised 100 wt% spherical powder was used as the reference powder with a flowability of 28 s to facilitate the tensile property discussion. It was found that the powder flowability is the crucial parameter governing the tensile properties of fabricated specimens. It was shown that the decrease in powder flowability (36.5 s) resulted in increases in susceptibility to the formation of a lack of fusion defects with dropped tensile properties. The microstructure of the fabricated Ti6Al4V alloy features the formation of prior beta grain boundaries and an alpha prime (alpha ') martensite. Furthermore, no intermetallic aluminide phase (Ti3Al) precipitations in grain boundaries were detected through energy-dispersive X-ray spectroscopy analysis.