Microstructure and properties of Al–Zn–Mg–Cu alloy fabricated by cold metal transfer additive manufacturing

Al–Zn–Mg–Cu alloy additive manufacturing components were fabricated by cold metal transfer advance (CMT-A) and metal inert-gas welding (MIG). The results indicate that the CMT-A as-deposited sample has fine grains with small-sized η'-strengthened precipitates and supersaturated solid solution, and the hardness is increased by 16.1% compared to the MIG as-deposited sample, and its peak aging hardness increased by 36.8% compared to the MIG. It indicates that CMT-A can directly produce Al–Zn–Mg–Cu products that have the potential to achieve high strength without the need for re-solutionizing.