Abstract: Based on the ANSYS software, a multi-physics finite element model was established to research the weld nugget formation during the weld-bonding process of three stacks of steel sheets. The contact resistance between the steel sheets with the adhesive was parameterized in this model to illustrate the effect of the adhesive on the weld-bonding process. The calculation results in the structure, electric and thermal field during the weld nugget formation were investigated and validated by the experiment. The research results show that the weld nugget formation in the weld-bonding joint with 0.8mm DC04, 1.4mm DP600 and 1.8mm DP780 is about 40ms earlier than that in the resistance spot welding joint under the same welding condition. The weld nugget formation between DP600 and DP780 is 80 ms earlier than that between DC04 and DP600 during the weld-bonding process.

Key words: three stacks of steel sheets; weld-bonding; weld nugget formation; finite element analysis