Influence of Arc Oscillation Modes on the Porosity and Mechanical Properties of Auxiliary Wire‐Filling Gas Metal Arc‐Directed Energy Deposition 2319–1100 Aluminum‐Based Functionally Graded Material

The influence of no arc oscillation, Z‐shaped arc oscillation, and spiral arc oscillation on the porosity, microstructure, and mechanical properties of 2319–1100 aluminum‐based functionally graded materials (FGMs) fabricated by auxiliary wire‐filling gas metal arc‐directed energy deposition (AWF‐GMA‐DED) was investigated. Spiral arc oscillation exhibited the best pore suppression effect, with lower porosity and smaller pore size than those obtained under no arc oscillation. As the ER1100 filling ratio increased from 10% to 35%, the maximum pore size under spiral arc oscillation decreased from 86.6 to 74.6 μm, compared with 129.5 to 77.5 μm under no arc oscillation. Compared with the tensile properties of specimens with no arc oscillation, the tensile strength of specimens with Z‐shaped arc oscillation in the corresponding deposition layer was increased by 3.56%–9.03%, and the elongation was increased by 0.27%–3.77%. The experimental results indicate that arc oscillation is an effective in‐process strategy for improving densification and mechanical performance in wire arc additive manufacturing of gradient structures.