Effect of thermomechanical treatment on the evolution of rolling and recrystallization textures in twin-belt cast AA5754 aluminum alloy

Abstract

The relative importance of shear banding, particles, and grain size in determining the rolling and recrystallization textures of a twin-belt strip cast AA5754 aluminum alloy has been investigated. Various thermomechanical processing schedules have been employed that incorporate homogenization, warm and cold rolling, and intermediate anneals in various combinations prior to a final recrystallization treatment. Despite its inherent susceptibility, the alloy undergoes limited shear banding during rolling and displays a large random component of the deformation texture. The effect is most pronounced in the as-cast alloy subjected to cold rolling without any prior or intermediate heat treatments. This can be attributed to the denser distribution of particles, a greater scattering of the initial texture, and a relatively small grain size. Homogenizing prior to cold rolling promotes more extensive shear banding and accelerates the development of a strong rolling texture. A grain shape effect results in a prominent S component in the rolling texture at higher reductions, irrespective of the processing history of the material. In the heavily rolled as-cast alloy, the recrystallization texture is dominated by Cube and R components indicating the prevalence of oriented growth processes. However, homogenizing the as-cast alloy prior to cold rolling imparts a characteristic recrystallization texture with strong CH component, which is most likely due to selected growth of grains following particle-stimulated nucleation.