Study on the transition behavior and forming process of oscillating laser double-wire welding of aluminum alloy

To achieve high-quality and high-stability weld formation in aluminum alloys, this study investigates the dynamic evolution of the molten pool and droplet transfer behavior during oscillating laser double-wire welding. Particular emphasis is placed on the coupled effects of process parameters—including laser power, laser oscillation parameters (frequency, amplitude, and trajectory), and wire feeding speed—on molten-pool morphology and weld quality. By employing high-speed imaging technology, the surface flow of the molten pool, droplet transfer, and metal filling behavior were captured in real time, revealing the influence of oscillation parameters on the stability of weld formation. Research indicates that different laser oscillation patterns—such as circular, ∞-shaped, and figure-eight trajectories—significantly modify the spatial distribution and fluctuation period of heat-source energy within the molten pool, thereby influencing the pool’s responsiveness to external energy input and material feed. A well-designed oscillation trajectory can effectively enhance convective flow within the molten pool and improve the stability of droplet transfer. This research further aims to construct a mapping relationship between droplet transfer and molten-pool response under various process parameters, and to establish a multifactor coupled model of “energy input–molten pool behavior-forming quality” providing both theoretical support and experimental evidence for high-precision control and process optimization in oscillating laser double-wire welding.