Control of through-thickness shear texture by asymmetric rolling

Large shear deformation was successfully introduced in 1050 aluminum sheet by differential roll speed rolling in high friction condition. The roll speed ratio was varied from 1.0 to 2.0. When roll speed ratio is smaller than 1.4, shear strain increases near the surface, however it decreases to zero at the midthickness. With the roll speed ratio larger than 1.6, shear strain is introduced even at the midthickness, and it increases near the surface. The shear strain increases with roll speed ratio. After 2-pass differential speed rolling, a large shear strain prevails throughout the thickness. The rolling direction of the second pass was so varied that the direction of shear deformation introduced in the second pass was similar (unidirectional shear rolling) or reverse (reverse shear rolling) to that in the first pass. The shear texture of which main components are {111}<110>, {112}<110> and {001}<110> prevails throughout the thickness, and conventional rolling texture such as {112}<111> or {123}<634> orientation cannot be detected in any part of thickness. The rolling direction of the second pass exerts a little effect on the deformation texture. After recrystallization annealing, shear texture components are retained. The intensity of shear texture components after recrystallization is almost similar to the deformation texture. The differential speed rolling, by which shear deformation can be introduced throughout the thickness, is proved to be promising process for improving physical and mechanical properties of the rolled and annealed aluminum alloy sheets by texture controlling.