Recently, many motor companies use adhesives in resistance spot welding process to improve the tensile and fatigue strength and to insure sound insulation. This paper deals with the spot welding process with adhesives such as dynamic resistance and temperature distribution by using the numerical analysis and experimental techniques.
The dynamic resistance was calculated by the current and voltage values measured by toroidal coil and voltage sensor, respectively. Several, significant results were obtained by investigating the dynamic resistance profile. The results of dynamic resistance with adhesives showed a higher magnitude than results without adhesives over the almost entire period of welding process. This difference was significant especially at the early stage of welding process. The contact resistance could be estimated from the dynamic resistance data and then used to simulate temperature distribution.
In general, numerical results have shown the nugget sizes smaller than experimental ones. On the other hand, the simulated HAZ(heat affected zone) was larger than that from experiments. Nugget and HAZ sizes with adhesives were larger than those without adhesives in both the numerical and experimental results. The adhesives also caused a slight increase in tensile strength of weldments.
