Complex Behavior of Forces Influencing Molten Weld Metal Flow based on Static Force Balance Theory

This study is aimed at investigating the forces responsible for the detachment of molten metal droplets formed at an electrode tip, which imminently and eventually drop into the weld pool during the welding process. The Equations used by Kim and Eagar in 1993 were applied to this study. It was found that the different detaching forces which are the gravitational force, the electromagnetic force, and the drag force, were determined to be 7.154 x 10-6N, 0.05N and 1.736N respectively. Whereas, the primary retaining force, which is the surface tension force, was calculated to be 0.0195N. From the findings, since the combination of the detaching forces taken together is greater than the retaining force, detachment of the molten metal droplet must inevitably occur. The combined effect of these forces on the behaviour of molten metal during the droplet detachment process was adequately investigated in this study.