A Review of Shunting Effect in Resistance Spot Welding

Abstract

Studies on shunting effect in resistance spot welding (RSW) have not been widely performed and limited researches were devoted to some aspects of it. Shunting effect in RSW occurs when the electrical current passes through the preceded spot welds in the case of multi-spot welding. The amount of this current depends mostly on weld spacing, and to some extent, on the number and size of previous spot welds. The phenomenon causes some changes in the quality of shunted weld, such as nugget diameter decrease with consecutive reduction of mechanical strength due to changes in electrical current distribution and temperature distribution. Recently some efforts have been made to develop equations for determine the relationship between the input welding parameters and the quality of spot welds. However, the problem needs deeper research and analysis. The paper reviews different approaches performed for simulation and analysis of shunting in RSW.