Effects of Initial Precipitate on Shear Deformation during Asymmetric Rolling of Al-Mg-Si Alloy: Texture and Formability

Al-Mg-Si alloy was rolled asymmetrically at several temperatures to apply shear deformation, and the effects of the initial precipitate on shear deformation, texture evolution, formability, and plastic anisotropy were studied. Texture was analyzed using a EBSD, and the formability and plastic anisotropy of the specimen were evaluated using the (r) over bar value and Delta r value calculated from the plastic strain ratio (r-value) which was determined from the change in the length of the specimen during tensile deformation. Asymmetric rolling induces a larger equivalent strain than symmetric rolling, and the equivalent strain increases as the asymmetric rolling temperature increases. When a specimen with peak-aged initial precipitates was asymmetrically rolled, less shear deformation occurred at room temperature than in a solution-treated specimen without initial precipitates. In contrast, a larger shear deformation occurred at high temperatures (500 degrees C). With asymmetric rolling at room temperature, the specimens without initial precipitates had higher formability and lower plasticity, while for asymmetric rolling at high temperature, the specimens with initial precipitates had higher formability and lower plastic anisotropy. This is due to the < 111 >//ND texture, such as {111}< 110 > and {111}< 112 > orientation that has similar and high r-values at 0 degrees, 45 degrees, and 90 degrees to the rolling direction, developed by the shear deformation that occurred during asymmetric rolling.