Durability of welded aluminium extrusion profiles and aluminium sheets in vehicle structures

Different approaches – the nominal stress, structural hot spot stress and notch stress approach – to analyse the fatigue strength of welded structures made from wrought aluminium alloys were studied. Experimental and numerical investigation was carried out for this purpose on detail specimens and components. The results shown here were generated during the research project “Extrusion profile and sheet metal structures of wrought aluminium alloys in vehicle construction” . The studies show that due to the existing guidelines, welds on structures made from aluminium alloys are sometimes designed very conservatively. It is possible to optimise and reliably design welded joints of thin sheet structures by applying the notch stress approach using the reference radius rref = 0.05 mm and the reference SN curves derived here.