A comprehensive review of Double-Pulse resistance spot welding for enhanced weld quality and mechanical performance

Abstract Resistance spot welding (RSW) has become a widely adopted joining technique in the automotive and structural manufacturing industries due to its high productivity, potential for automation and cost-effectiveness. However, conventional joining using single-pulse RSW frequently suffers from unstable nugget formation, expulsion, excessive heat accumulation and uneven mechanical performance, particularly in dissimilar material joints and advanced high-strength steels (AHSS). The Double-Plus Resistance Spot Welding (DP-RSW) method has emerged as an improvement where advanced current modulation approach enhances the quality of the joints formed by using a pre-heating pulse, an inter-pulse cooling phase and a subsequent high-current main pulse. This review critically examines the operating principle of DP-RSW process, temperature behavior, and properties of the weldments. A comprehensive discussion is presented of the impact of DP-RSW on nugget formation, tensile shear strength, failure energy, microstructural evolution and hardness distribution. When compared to conventional single-pulse welding it was found that DP-RSW provided superior temperature control, greater nugget consistency, decreased expulsion, narrower heat-affected zones and improved mechanical performance. Further, the applicability of DP-RSW in welding AHSS, stainless steels and dissimilar steel combinations used in lightweight automotive structures have been highlighted. Finally, recent developments in numerical modeling, statistical optimization, artificial neural networks and evolutionary algorithms for process optimization are summarized along with research gaps and future direction.