A Transient Unified Model of Arc-Weld Pool Couplings During Pulsed Spot Gas Tungsten Arc Welding

A. Traidia[1], and F. Roger[2]
[1]AREVA NP, Technical Center, Saint Marcel, France
[2]ENSTA Paristech, Paris, France

Using COMSOL Multiphysics, a finite element model is introduced in this paper to describe the couplings between the welding arc and the weld pool dynamic in pulsed gas tungsten arc welding. The cathode, arc-plasma and melting anode regions are taken into account. The unified time-dependent model describes the heat transfer, fluid flow and electromagnetic fields in the three regions. The originality of the numerical model is its ability to treat the arc and weld pool time evolution under pulsed current welding in a unified formalism, taking into account eddy current in the weld pool. A comparison between the pulsed current welding and the corresponding mean current shows that they are energetically equivalent but produce different weld pool shapes. We can conclude that for a given level of energy, it is more interesting to use a pulsed current welding to get a greater weld shape.