Variations of the improved characteristics on microstructure and mechanical properties of Al–Cu alloy fabricated by magnetic field assisted wire-arc additive manufacturing after heat-treated

In this investigation, Al–Cu alloy was used for wire-arc additive manufacturing experiment with and without assisted longitudinal magnetic field (ALMF) introduced, subsequently, heat treatment was conducted, aiming to investigate the variations of the improved characteristics brought by ALMF on microstructure and mechanical properties after heat-treated. The results indicated that the improved pores condition brought by ALMF was greatly weakened after heat-treated, while the promotion for the columnar to equiaxed transition and the improvement to precipitation remained. As for mechanical properties, the improvement of the uniform distribution of microhardness by the ALMF deteriorated. Moreover, the optimisation brought by ALMF on reducing the anisotropy of tensile strength was greatly weakened, and the improvement of elongation disappeared.