Effect of droplet transfer mode on composition homogeneity of twin-wire plasma arc additively manufactured titanium aluminide

Twin-wire plasma arc additive manufacturing (TW-PAAM) is an innovative process for titanium aluminide manufacture which low in equipment cost and high efficiency. However, as situ alloying process, the composition homogeneity typically a source of concern. The present work investigates this subject by observing element input mode at various welding wire positions with high-speed camera system particle tracking method. It found that when wires are position, droplet enters molten pool from tip wire, alloy interval long, resulting formation bands aluminium content edge deposition layer. When close to workpiece surface, transfer switches mixture dual wire-bridge Ti transfer. diameter droplets decrease, well heterogeneity conclusion establishes correlation between homogeneity, beneficial optimizing TW-PAAM fabrication process.