<p>The wire-powder synergistic arc additive manufacturing method combines the advantages of both wire-based and powder-based additive manufacturing while maintaining low costs. This work investigates the effects of copper content on the microstructure and properties of Ti-xCu alloys fabricated. The research examines the microstructural composition of Ti-xCu alloys (<i>x</i> = 4, 7.3, and 10 wt.%) and the precipitation mechanisms of Ti₂Cu during solidification. Research has shown that the microstructure of Ti-xCu alloys is composed of a basket-weave Widmanstätten structure. With the increase in Cu content, the relative content of original <i>β</i> grains, lamellar α phase, lamellar α phase thickness, and α bundle size in the tissue gradually decreases, while the interlayer α spacing gradually increases. Moreover, the morphology of the Ti₂Cu phase has changed significantly. The grain refinement and increased precipitation of hard Ti₂Cu phase raised the hardness value by 22% (from 294 HV in Ti-4Cu alloy to 358 HV in Ti-10Cu alloy). Enhanced solid solution of Cu atoms in the α-Ti matrix and promoted precipitation of Ti₂Cu as an intermetallic compound. The synergistic effects of these mechanisms improve the yield strength and ultimate tensile strength, while reduce the elongation value. The corrosion resistance demonstrates an initial increase followed by a decrease, primarily governed by Ti₂Cu morphology, where granular Ti₂Cu phases exhibit superior corrosion resistance.</p>