Dynamic analysis of metal transfer in GMAW: modeling and experiments

In this work, a pulsed welding process has been investigated to highlight how a time varying profile of current impacts on the metal transfer dynamics. First, the process has been recorded using high-speed camera, allowing to qualitatively evaluate the effectiveness of metal transfer and the synchronization of the droplet detachment with current peaks. Second, a time-dependent axi-symmetric 2-D model has been developed in the FLUENT environment to take into account both the droplet detachment using a volume of fluid (VoF) model and the production and diffusion of metal vapour through a simplified diffusion model (neglecting demixing effects). We report a comparison between experimental and simulative results of a pulsed transfer mode for a steel wire (d = 1 mm) and an Ar shielding gas.