The influence of arc swing process in wire arc additive manufacturing on the microstructure and properties of 2219 aluminum alloy

Abstract Aluminum alloy has been widely used in aerospace and medical equipment fields due to its excellent comprehensive performance. This experiment innovatively applied the arc swing process to successfully prepare single-pass multi-layer stacked specimens by regulating different welding rates and deeply explored the effect of this process on the microstructure and mechanical properties of 2219 aluminum alloy arc additive formed parts. Experimental data shows that welding rate is a key factor affecting the internal defects and mechanical properties of the specimen. The components formed by swing arc technology have a uniform and dense fish scale surface morphology, demonstrating excellent forming accuracy. The unique swinging wire feeding method effectively promotes grain refinement in the sedimentary layer, forming a uniform equiaxed crystal structure. Microscopic analysis reveals that copper element undergoes segregation in the grain boundary region in the form of Al Cu eutectic phase. When the welding rate was controlled at 8 mm/s, the sample achieved optimal comprehensive performance: porosity was reduced to the lowest level, tensile strength reached 264.83 MPa, and elongation was 12.59%. Observation of the fracture morphology shows that there are numerous micro porous defects on the fracture surface, exhibiting typical transgranular fracture characteristics. These research results provide an important theoretical basis and practical guidance for optimizing arc swing additive manufacturing process parameters and improving the performance of aluminum alloy components.