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Abstract Additive friction stir deposition (AFSD) is a novel additive manufacturing technique that enables the fabrication of components in the solid state. Given the benefits of AFSD, understanding the behavior of various feedstock materials after undergoing the AFSD process is crucial for optimizing their performance in structural applications. This study aims to evaluate the effects of AFSD on an Al–Mg alloy, Al5086, comparing it to its initial H32 condition to assess the changes in mechanical properties, microstructure, corrosion resistance, microhardness, and electrical conductivity. Tensile testing showed a 23% reduction in yield strength for as-deposited samples, while ultimate tensile strength remained comparable to the feedstock. Ductility improved significantly, with elongation to failure increasing by 77%, attributed to grain refinement and dynamic recovery. Microhardness decreased by 16% in lower layers due to thermal exposure, but electrical conductivity remained stable, indicating minimal solute atom redistribution. The Nitric Acid Mass Loss Test (NAMLT) revealed a 245% increase in corrosion rate for the AFSD material, linked to the higher density of grain boundaries acting as pathways for corrosion. These findings highlight AFSD’s potential for improving ductility and formability. However, they underscore the need for optimization to reduce corrosion susceptibility and address mechanical strength trade-offs. Future work should focus on fine-tuning process parameters or implementing post-treatment methods to enhance corrosion and mechanical performance. 

Abstract Additive Friction stir deposition (AFSD) has been extensively utilized for processing Al alloys. The properties of the Al depositions under as-fabricated state, including mechanical strength and corrosion resistance, are typically inferior compared to the base material, especially for heat-treatable alloys. In this research, multilayers of Al7075 composites, reinforced by ceramic particles, were processed by AFSD to evaluate the effect of using feedstock materials containing reinforcing particles on the properties of the deposition. For comparison, a bare Al7075 part was also processed by AFSD under the same conditions. The results of mechanical testing revealed a significant reduction in the microhardness, tensile strength and compression stress of the bare alloy after deposition. However, the composite deposition exhibited only a slight decrease in the properties compared to its feedstock material. Additionally, the corrosion resistance of the composite enhanced after AFSD, in contrast to the bare alloy, where the corrosion resistance deteriorated. Microstructural analysis showed a uniform distribution of the reinforcing particles in the matrix for the deposition, closely resembling that of the feedstock composite. This, along with grain refinement and minimal change in precipitates, were the reasons for the minimum changes in mechanical properties, as well as the improvement in corrosion resistance.