Study for the Arc Phenomena of TIG-MIG Hybrid Welding Process by 3D Numerical Analysis Model

Hybrid welding process is effective technique to solve the problem of the welding execution by combining the merit of various heat sources. However, the hybrid welding process is complicated by interaction of the heat sources and selection of the suitable welding condition is difficult. The numerical analysis enables to investigate an influence of each parameter on hybrid arc phenomena theoretically. In this study, we simulated the influence of the hybridization condition such as TIG current and torch angles on the TIG-MIG hybrid arc phenomena. The main results are as follows: (1) Repulsion between TIG and MIG arc depends on the distance between the tip of both electrodes. (2) More than certain degree of TIG and MIG torches that is cross each other causes formation of direct current path between both electrodes. (3) The direct current does not increase so much with TIG current and reaches upper limit in certain value. When the TIG current is over the limit value, all increase current flow forward the base metal, and contributes to heat input.