Abstract: An axisymmetric finite element model is developed to simulate the temperature field of resistant spot welding according to the process of nugget formation of three layers stainless steel sheets. A simulation method of the interaction of electrical and thermal factors is presented. Computed results show in the early stages of nugget formation, a small nugget which comprised up and down faying surfaces and middle sheet is firstly developed. With time prolonging, the nugget then develops along the axial and radial direction. Experimental verification shows that the model prediction agrees well with the practical. This model provides a useful basis for the analysis of temperature field and stress filed of resistance spot welding for multi-layers sheets.

Key words: Finite element method, Numerical simulation, Resistance spot welding, Temperature field