| Anisotropy and texture plays an important role in deformation of Aluminum alloy sheets. The development of anisotropy during metal forming is a key factor as in the standard industrial use of AA -- 6022 as stamped automotive body enclosures where a close estimation of anisotropy can deduct costs on both machinery and inventory. In this thesis, we provide a methodology to predict the anisotropic behavior of polycrystalline metals depending on its processing history. The methodology suggested is based on single crystal plasticity model of Cuitino and Ortiz where the mechanics of dislocation motion through forest dislocations is estimated statistically. In that context, we first study the role of uncertainties and responses of the initial parameters such as initial yield stress and dislocation density. R-values, which is a measure of anisotropy, of a sample undergone hydraulic bulge test are obtained by a uniaxial tensile test simulation and found to be in good agreement with the experimental findings. An optimization method to capture the texture while reducing the number of orientations is introduced and compared with random sets of orientations. Gradual work hardening effect is captured by adjusting the dislocation density carried over through consecutive simulations of rolling and uniaxial stretching. However more accurate models of rolling simulations is necessary to provide r-values and work hardening effect without the need of texture. |
