Research on shape control and performance of joint nugget during RSW processing

A control method for containing the nugget morphology of the resistance spot welding (RSW) joint through the design of the special electrode structure is proposed, and numerical simulation analysis was used to study the current and temperature field distribution and variation characteristics of RSW joints under the structural condition of ring conductive electrode (RCE), revealing the effect of ring conductive electrode (RCE) structure on the mechanism governing the formation of nugget morphology in joints. Numerical simulation analysis and the resistance spot welding (RSW) process tests show that the special structure of RCE makes the RSW heat reasonably distributed and effectively used, and the peak temperature is significantly reduced. Compared with the general RSW nugget, the morphology of the nugget under the RCE condition shows that the penetration rate is further reduced without reducing the diameter of the nugget. The joint surface indentation is reduced obviously, and the surface quality is improved effectively.