Prediction of the texture evolution during forming of an 6016 aluminum alloy based on VPSC and macroscopic anisotropic model

Abstract

In this study, we present a computationally efficient way to predict the deformation behaviour and texture evolution during mechanical tests and sheet metal forming operations. A two-pronged approach is developed. An orthotropic yield criterion that represents with accuracy the engineering level material’s anisotropy and ensures computational efficiency is used to simulate the deep drawing process. The finite-element (FE) predicted strains are further used to inform the visco-plastic self-consistent (VPSC) crystal plasticity model to predict the texture in different regions of the fully drawn cylindrical cup. This approach is illustrated for a strongly anisotropic aluminium alloy. For this purpose, the available data from uniaxial tensile tests were utilised to determine the anisotropy coefficients associated with the orthotropic model and the crystallographic slip hardening parameters for the VPSC model, respectively. The capabilities of the VPSC model are first illustrated by comparing the experimental and predicted stress-strain response for various orientations as well as the anisotropy in the Lankford coefficients and post-test textures. Furthermore, using VPSC the evolution of plastic anisotropy during deep drawing process was also systematically studied and comparisons with available textures from various locations on the cup are reported. The good agreement with data show that this approach leads to accurate results while preserving computational efficiency.