Experimental and XFEM study on the effect of clamping on the fatigue behavior of AA5182 resistance spot welds

This study investigates the effect of clamping on fatigue behavior and crack propagation in resistance spot-welded (RSW) AA5182 aluminum alloy, with particular emphasis on heat-affected zone (HAZ) cracking. Comparative experiments were performed on clamped and unclamped specimens fabricated under identical welding parameters to assess weld quality and mechanical performance. An Abaqus/Standard extended finite element method (XFEM) model with a Paris-law formulation in terms of energy-release rate , was developed to simulate crack nucleation at the faying interface and subsequent propagation under cyclic loading. The results, demonstrated that failure mode depends on stress regime. At higher loads (low-cycle fatigue), interfacial shear dominated, while at lower loads (high-cycle fatigue), HAZ-initiated cracking prevailed. The integration of experimental observations with XFEM predictions confirmed the beneficial role of clamping in stabilizing crack initiation sites and delaying fatigue failure.
These findings underscore the importance of clamping in mitigating HAZ cracking, improving weld reliability, and optimizing fatigue performance of lightweight aluminum structures joined by RSW.