MECHANICAL PROPERTIES AND FATIGUE BEHAVIOR OF ALUMINUM ALLOYS JOINED BY CO2 LASER WELDING: A REVIEW

Ihsan KIRIK ¹

Due to its high energy density and flexibility, laser welding of aluminium alloys has gained significant prominence in high-performance sectors such as aerospace, automotive, and the chemical industry. This study provides a comprehensive review of current laser welding technologies for aluminum alloys, with a focus on metallurgical challenges and the mechanical properties of the joints. Unlike conventional arc welding, precise control over various process parameters is required for laser welding of aluminium to mitigate common defects. A critical analysis of the literature suggests that, regardless of its spatial location within the weld, porosity remains the primary factor that degrades fatigue strength. This research notably distinguishes between technical porosity, which can be eliminated through parameter optimisation, and metallurgical porosity (e.g., hydrogen- or metal vapour-induced), which tends to localise near the weld surface. Although CO² and modern fibre laser technologies have improved the reliability of these joints, this study reveals an ongoing gap in the literature concerning the fracture toughness, detailed microstructural characterisation, and long-term fatigue behaviour of specific laser-welded aluminium alloys. This review serves as a technical foundation for future research aimed at optimising joint integrity in structural applications.

Keywords
Al and alloys, Laser welding,, CO2 laser welding, Mechanical properties, Fatigue behavior,