Transient Analysis Of Molten Pool With Applying Axial Magnetic Field In Tig Arc Welding

In TIG arc welding, technicians use a rolling technique to ensure high quality welds. In this rolling technique, the cathode is rotated while welding. However, the rolling method is difficult and complicated. As a countermeasure, it has been proposed that a magnetic field is applied to rotate the arc. When a magnetic field is applied, it is difficult to measure the arc behavior and the convection of the molten pool. Hence, numerical methods for the arc have been developed [1] , [2] . Moreover, the arc behavior is analyzed with applying magnetic field [3] . In this paper, molten pool with applying axial magnetic field in TIG arc welding transient was analyzed. Specifically, analytical model was constructed for solid, liquid, and gas, and four forces were calculated for the molten pool. The four forces are drag force of plasma flow, shear stress of Marangoni effect, buoyancy, and electromagnetic force. As a result, a spiral flow velocity was generated in the molten pool with the application of axial magnetic field. In addition, the flow velocity of the molten pool was more affected by the axial magnetic field than that of the arc. Therefore, it was possible that transient analysis of molten pool with applying axial magnetic field in TIG arc welding.