Modeling and simulation of the metal transfer on GMAW-S process

The GMAW-S process occurs from sequences of arcing and short-circuit welding periods. For modeling purposes, many researchers believe that the metal transfer occurs only in the period of short circuit (consideration to be taken into account in the present work), in which the link between the electrode and the welding pool is generated through a liquid metal bridge. From this exact moment, it can be observed changes in the metal bridge geometry due to electromagnetic (pinch effect), gravitational, and surface tension forces. This paper is aimed to model the dynamic geometry of metal bridge during the short-circuit period, considering the fusion and feed rate electrode wire balance. This model was represented by state equations building from applying Kirchoff’s, Lorentz, Young–Laplace law, Bernoulli’s principle, the equation of fluid continuity, and concepts of analytic geometry. The model implementation was developed in Simulink and could be used to study the metal transfer control, as well as, the appropriate welding parameters selection, aiming to achieve a higher level of welding quality.