| Abstract Scope |
Wire-based directed energy deposition (Wire-DED) is of interest for fabricating large CuNi alloy components due to the potential for reduced lead times compared to conventional casting-based supply chains. This study investigates the microstructural and mechanical evolution of a Wire-DED, Ti-modified 70Cu-30Ni build in both as-built (AB) and heat-treated condition. Samples were extracted from different locations in the build to analyze through-thickness variations. Advanced characterization techniques, including XRD, EBSD, SEM, and TEM, revealed significant insights into texture, grain morphology, secondary phase precipitation, and compositional segregation. In the AB condition, through-thickness hardness mapping and SEM analysis showed location-dependent variations in strength, dendrite arm spacing, and Cu-Ni segregation. Aging at 600°C, 650°C, 700°C, and 800°C induced the precipitation and coarsening of Ti-rich phases, which resulted in notable increases in alloy strength. Results of these evaluations are compared to similar data obtained from CuNi alloys fabricated via laser powder bed fusion. |