Mechanical behavior of resistance spot welded, adhesive bonded, and hybrid joined AA5182

Abstract This study investigates the mechanical performance of AA5182 aluminum alloy joints produced using resistance spot welding (RSW), adhesive bonding, and hybrid RSW–adhesive techniques. The joining processes were carried out under controlled and automated conditions, with adhesive layers applied at six different thicknesses ranging from 0.50 to 1.25 mm. Tensile T-peel tests were employed to evaluate joint strength and quality. The results revealed that spot-welded joints exhibited the lowest peel strength (220.5 N), mainly due to localized stress concentration at the weld nugget. Adhesive joints demonstrated a progressive increase in strength with thickness, reaching a maximum of 327.2 N at 1.25 mm. The highest performance was observed in hybrid joints, which combined the mechanical interlocking of spot welds with the load distribution of adhesives. The maximum load in hybrid joints reached 616.7 N, corresponding to an improvement of approximately 180 % compared to spot welding and 88 % compared to adhesive bonding alone. Fractographic analyses indicated brittle fracture at weld nuggets, mixed cohesive/adhesive failure in bonded joints, and combined fracture mechanisms in hybrid joints. These findings confirm that hybrid joining provides superior mechanical behavior and represents a promising solution for lightweight structural applications in the automotive and aerospace industries.