Effect of Laser Quenching on Wire–Powder Collaborative Arc Additive Manufacturing of Ti6Al4V-Cu Alloys with 2.4% and 7.9% Copper Content

In this work, Ti6Al4V-Cu alloys with different Cu contents (2.4 and 7.9 wt.%) were fabricated using novel wire-powder synchronous arc additive manufacturing to analyze the effect of laser quenching on Ti6Al4V-Cu alloys. The results show that this method can successfully produce Ti6Al4V-Cu alloys with a uniform composition. As the copper content increased, the alloy transitioned from a Widmanstätten structure to a basketweave structure, and the yield strength and tensile strength of the alloy increased by approximately 35% due to grain refinement and the high volume fraction of Ti₂Cu with eutectic lamellae. The microhardness of the alloys significantly increased after laser quenching, particularly for those with low copper contents (from 311 HV to 510 HV). Laser quenching also enhanced the corrosion resistance of the alloy in a 3.5% NaCl solution.