Formability of friction-stir-welded dissimilar-aluminum-alloy sheets

Friction stir welding (FSW) was investigated as a method for joining dissimilar-aluminum alloys 5182-0,5754-0, and 6022-T4. These alloys are used in automotive applications in which parts consisting of dissimilar welded combinations of these alloys may:be of interest. This study focuses on the formability of friction-stir-welded, dissimilar-alloy pairs of essentially the same gage, in order to investigate the mechanical properties that can be obtained using this approach: Testing showed that the properties of welded 5182/5754 alloy pairs retained reasonably good formability compared to base material performance. However, the 5182/6022 and 5754/6022 alloy pairs had significantly reduced formability compared to the base material properties, with failures occurring in the heat-affected zone (HAZ) of the 6022 or in the weld nugget itself. However, this level of formability was not much worse than that of monolithic, friction-stir-welded 6022.