23. Internationales Stuttgarter Symposium

Automobil- und Motorentechnik

4. - 5. Juli 2023

Session: VEHICLE DYNAMICS & SIMULATION | | 12:00 - 12:30

Lightweight Potential and Crash Performance of friction stir welded Tailored Blanks

Maximilian Bachmann, Institut für Umformtechnik

In former papers methods to join different aluminium or different steel sheets having same thicknesses are presented using the friction stir welding process with flat tools. In order to increase the lightweight potential, the Materials Testing Institute of the University of Stuttgart, developed a novel variant of the friction stir welding process, enabling the joining of aluminium and steel sheets of different thicknesses. Compared to the conventional welding method, the difference relates to the stir welding tool used, which consists of a stepped welding pin and allows combined lap-and-butt joints to be produced. Potential applications for this innovative joining technology include lightweight components for car bodies. In this context, this paper aims to demonstrate the lightweight potential and the crash performance of Tailor Welded Blanks (TWBs) made from DX54(1 mm) and AL6016 - T4 (2 mm). For this purpose, possible parts of a car body that can be replaced with these TWBs were identified first. Subsequently, these parts were constructively integrated into a selected car structure, which was finally used to perform crash simulations with front and side impacts. To demonstrate the benefits of the new joining technology, the calculated crash results were compared with those of conventional car bodies and the advantages of the used TWBs were highlighted. Concretely, the friction stir welded TWBs enable vehicle weight to be reduced while providing comparable properties to those of currently used components, thus lowering CO2 emissions during car use.