Abstract: Up till now, most of the researchers believe that there are four kinds of forces in the weld pool convection, they are surface tension, electromagnetic force, buoyancy and gas shear stress. So electromagnetic force is very important, especially when large current is applied. In most of previous models, the electromagnetic force is calculated analytically, in which only the axial component of current is considered. Actually the radial component of current has the same effect, and may be advanced in some locations. In double-sided arc welding process, instead of the earth clamp, another torch is placed on the opposite side, the current will go from one torch, through the weld zone, to another torch. In this case, the current is more concentrated in the weld zone, the electromagnetic force will have significant effect compared with conventional welding process. In this paper, a new method of numerical calculation for electromagnetic force is developed, in which both axial and radial components are considered. And as an example, the distribution of electromagnetic force in double-sided arc welding is calculated. It demonstrates that this new method could give more accurate simulation of electromagnetic force, and is close to the actual process.

Key words: Electromagnetic force, Numerical simulation, Double-sided arc welding process