Current flow analysis in resistance spot welding

This paper present theoretical and experimental studies about the current flow during resistance spot welding processes. The finite element method where used in modelling and analysis of the electrical phenomena. The study presents the electrode geometry influence upon the current density pattern, both in the very early stage of welding (in the presence of the contact resistance) and at the end (in the presence of the melted nugget). The current density pattern is used to explain the toroidal initiation of the nugget, observed in the initial stage of the welding.(1, 2)