Microstructure characterization and properties of wire arc additive manufactured ERCu alloy

This study investigated microstructural evolution, electrical and thermal conductivity, mechanical properties under varied pulsed current frequency (DC, 1 Hz, 5 Hz, and 10 Hz) of ERCu fabricated by WAAM. Microstructural analysis reveals non-uniformly distributed coarsened columnar grains, attributed to complex thermal cycling. Microhardness exhibits a non-monotonic relationship with pulse frequency, reaching maxima under DC and 10 Hz conditions, which correlated with the variation of thermal input and molten pool kinematics properties. Specimens display anisotropic tensile properties: horizontal orientations exhibit the higher yield strength than vertical counterparts due to grain orientation effects. The electrical conductivity and thermal conductivity remained consistent with the properties of the metal wire. These findings establish a highly valuable pathway for efficient manufacturing of Cu components.