Production of Pre-Alloyed Ti–6Al–4V Powders from Titanium Sponge via a Combined Mechanical Alloying and Hydrogenation–Dehydrogenation Process for Powder Metallurgy

Ti–6Al–4V is the primary titanium alloy for aerospace, biomedical, and additive manufacturing applications; however, the high cost of powders produced by atomization limits their widespread adoption. This study aims to develop a cost-effective method for producing chemically homogeneous pre-alloyed Ti–6Al–4V powders from titanium sponge. A combined process is proposed, involving the hydrogenation of titanium sponge, mechanical alloying of the hydride phase with Al and V powders, and subsequent vacuum dehydrogenation. The formation of the brittle δ-TiH2 phase facilitated intensive material comminution and effective distribution of the alloying elements. According to laser diffraction data, the median particle size decreased from 450 to 30–35 µm. X-ray diffraction (XRD) analysis confirmed the sequential α-Ti → δ-TiH2 transition and the formation of a stable α + β two-phase structure characteristic of Ti–6Al–4V following dehydrogenation. SEM observations demonstrated that the final powders predominantly consist of individual fractured particles with limited hard agglomeration, favorable for powder flowability and compaction behavior. EDS analysis indicated a relatively homogeneous microscale distribution of Al and V without observable large-scale segregation. The synthesized powders exhibited low impurity levels, with O < 0.07 wt.% and H < 0.02 wt.%. The developed approach represents a promising and economical alternative to expensive atomization techniques for powder metallurgy and additive manufacturing.