Experimental Study of Imperfections in Longitudinally Welded AW‐5083‐H321 Aluminium Alloy Members

Welding of aluminium alloys presents many challenges, the most notable being strength reduction in the heat‐affected zone and pronounced welding‐induced deformations. Consequently, longitudinally welded aluminium members have been poorly studied, with existing experimental data both sparse and largely outdated. With the ongoing development of welding processes that enable metal fusion with lower heat input and potentially less degradation in the heat‐affected zone, updating this database is essential. This paper presents an experimental investigation aimed at quantifying imperfections inherent in longitudinally welded aluminium members fabricated using modern welding processes. Eight I‐section members, fabricated of the alloy EN AW‐5083‐H321 using the DC‐MIG‐P and AC‐MIG‐P welding processes, were investigated. Residual stresses were measured by X‐ray diffraction, HAZ extents were determined through hardness tests, and 3D scans were used to capture geometric imperfections. The measured HAZ extents were significantly below the values codified in Eurocode 9. In contrast, the geometric tolerances specified in EN 1090‐3 were not met for all specimens, despite the application of strict fabrication measures.