Two coarse-grained AA5182 alloys with as-received grain sizes 21 and 37 µm have been evaluated with respect to their superplastic properties. They exhibited moderate elongation to failure reaching maxima in excess of 350% at strain rates 10-2 s-1 and at 425°C and above 475°C, respectively. A correlation of the local strain distribution across the deformed gauge, with the volume fraction the most prominent texture components, showed that in the uniformly deformed segments, the cube texture dominates all other components. Occasionally, some regions proved softer, i.e. the majority of their grains comprising these were easier to deform that those in adjoining regions. In such cases, the post-mortem shape of the gauge showed secondary necking instabilities whose texture revealed increase of the Goss component at the expense of the corresponding cube texture (i.e. increase in the component demonstrating recrystallization). Most of the deformation was carried out in areas showing extreme grain refinement, with grains having size between 10 – 15 µm. Failure, however, occurred due to excessive dynamic recrystallization at the primary instability leading to grains whose size often exceeded 100 µm. It seems that the large amount of precipitates in the low cost AA5182 is capable of inhibiting dynamic recrystallization in most of the uniformly deformed regions of the gauge, but at regions where the local strain exceeded 15 the changes of the microstructure where so excessive that recrystallization and ultimate failure could not be prevented. The relatively large elongation to failure and the microstructure evolution during deformation promise smooth and uniform two-dimensional deformation and if that is the case then AA5182 will be particularly attractive in future application in the automotive industry.
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