Qualification of the hybrid metal extrusion & bonding (HYB) process for welding of aluminium offshore structures

Abstract

In the present investigation the aptness of the HYB process for butt welding of 4mm AA6082-T6 profiles is evaluated and benchmarked against one gas metal arc (GMA) weld and one friction stir (FS) weld, representing best practice for both methods. The tensile testing shows that the yield strength of the HYB weld exceeds that of the GMA weld and is comparable with that of the FS weld. When it comes to impact toughness the HYB weld is the superior one of the three. Since the subsequent transverse bend testing did not reveal any evidence of bonding defects or crack formation, it means that the 4mm AA6082-T6 HYB butt weld meets all acceptance criteria being specified by Equinor for offshore use.