Microstructure and mechanical properties of S217 nickel aluminum bronze alloy fabricated by wire arc additive manufacturing

Nickel aluminum bronze (NAB) is widely used in marine applications for its corrosion resistance and mechanical properties. Wire Arc Additive Manufacturing (WAAM) offers a cost-effective method for producing large-scale metal components, though research on WAAM-NAB is limited. This study investigated the microstructure, phase composition, and mechanical properties of WAAM-NAB. A single-wall component was successfully fabricated. The grains in the middle regions are larger than those in the top regions, and these grains have a weak texture. The alloy primarily contains α phases, retained β phases, and κ intermetallic phases (κ_III, κ_II, κ_IV). The microhardness is uniform, averaging 181.2 HV_0.3. Compared to cast NAB, WAAM-NAB shows superior mechanical properties, with minimal differences between vertical and horizontal directions. This research provides insights into the microstructure and performance of WAAM-NAB for marine applications.