Effect of intermediate annealing and reduction ratio on the texture evolution and formability in AA5083

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In the present study, the effect that intermediate annealing (IA) and reduction ratio (RR) exert on the microstructure and texture evolution in AA5083 sheets was investigated. The initial hot-rolled AA5083 sheet was subjected to the following thermomechanical process: primary cold rolling (CR-1) → intermediate annealing (IA) → secondary cold rolling (CR-2) → final annealing (FA). A reference (Ref) specimen was subjected only to CR-1 → CR-2 → FA with no IA process. Through-thickness microstructural heterogeneities were observed in the initial hot-rolled AA5083 sheet, and these features persisted in the CR-1 and IA specimens. The CR-2 and FA specimens, however, showed no through-thickness heterogeneities. Cold rolling enhanced the plane-strain texture components (Copper, Brass and S) whereas annealing enhanced the recrystallization texture components (Cube and ND-Rotated-Cube (RC)). Following FA, the non-IA (Ref) specimen showed a larger fraction of Cube and ND-RC components by comparison with specimens that had undergone IA. When the r-values predicted using the visco-plastic self-consistent (VPSC) model were compared with the experimental results, the r-value for the non-IA (Ref) specimen was smaller than those for the IA specimens after FA. The average r-value increased gradually (in a 45° direction) as the RR of CR-2 was decreased (70–40%). Controlling the RR of the CR-2 after IA resulted in isotropic sheets with enhanced formability. The largest r-value was observed in FA specimens with a small RR during CR-2. A balance between retaining deformation texture and the evolvement of the Cube component was responsible for the larger r-value.