Numerical Simulation in high efficiency spot welding

Resistance spot welding, hereinafter referred to as spot welding, is one of the most important methods for metal sheet welding used in industries such as the automobile, electronics, and so on. This welding is faster than other welding process such as arc welding process, laser welding process. Since high efficiency is required in this welding, welding in a short period is, required. Conventional resistance spot welding takes several hundred mili seconds to weld. Welding method in a short period less than 20 ms is developed. In order to find the optimum welding condition, 3D simulation model of spot welding in a short period was made in this research. The model based on electrical, thermal, and structural phenomena is required in this simulations. Numerical simulations were carried out by using Marc/Mentat software which had advantage of nonlinear analysis. The materials parameters were determined based on a contact domain between base metal and electrode. The validity of the 3D numerical model was verified by comparing the numerical simulations and the experimental results. The nugget size under various welding current was investigated. Since the experimental results and analytical results of this study showed almost the similar results, the validity of the proposed model was verified. © 2017 Japan Welding Society. All rights reserved.