A study on the formability of aluminum tailor welded blanks produced by friction stir welding

Tailored welded blanks (TWBs) technology can give an important possibility to obtain components in automobile industry satisfying lightweight strategies as well as satisfying increased crashworthiness, corrosion resistance, and accuracy. Friction stir welding (FSW) is a joining process, which can be well fitted to obtaining aluminum tailored blanks when compared to other conventional joining processes. This paper presents an experimental study on TWBs produced by FSW with dissimilar aluminum alloy thin sheets. The formability performance is investigated by obtaining forming limit curves with Nakajima test using different blank widths. The properties of welded AA5182/AA6061 alloy pair, 1 mm thick, are studied and the corresponding formability is compared to base materials. Different weld line orientations are defined related to sheet rolling direction and corresponding forming limit curves are obtained in addition to load-displacement behavior. Results show a dependency of TWB formability on weld line orientation, as well as a decrease of welded pair alloy formability when compared to base materials.