Understanding the influence of alloying elements on the print quality of powder bed fusion-based metal additive manufacturing: Ta and Cu addition to Ti alloy

Alloy design coupled with metal additive manufacturing (AM) opens many opportunities for materials innovation. Investigating the effect of printing parameters for alloy design is essential to achieve good part quality. Among different factors, laser absorptivity, heat diffusivity, and in situ intermetallic phase formations are critical. In this study, the first step employed was a reduction in Al and V contents in Ti6Al4 V to design Ti3Al2 V alloy, and further 10 wt.% tantalum (Ta) and 3 wt.% copper (Cu) were added to Ti3Al2 V. A synergistic effect of Ta and Cu addition in Ti3Al2 V negated their effect with higher porosities in Ti3Al2V-Ta-Cu. Ti3Al2V-Ta composition was more sensitive to the laser power, whereas Ti3Al2V-Ta-Cu to the overall energy density. Understanding the effect of energy density on these alloys' microstructural evolution and mechanical properties highlights the need for process-property optimisation during alloy design using AM.