Formation of Deformation Textures in Face-Centered-Cubic Materials Studied by In-Situ High-Energy X-Ray Diffraction and Self-Consistent Model

摘要

The evolution of deformation textures in copper and á brass that are representative of fcc metals with different stacking fault energies (SFEs) during cold rolling is predicted using a self-con?sistent (SC) model. The material parameters used for describing the micromechanical behavior of each metal are determined from the high-energy X-ray (HEXRD) diffraction data. At small reductions, a reliable prediction of the evolution of the grain orientation distribution that is represented as the continuous increase of the copper and brass components is achieved for both metals when compared with the experimental textures. With increasing deformation, the model could characterize the textures of copper, i.e., the strengthening of the copper component, when dislocation slip is still the dominant mechanism. For á brass at moderate and large reductions, a reliable prediction of its unique feature of texture evolution, i.e., the weakening of the copper component and the strengthening of the brass component, could only be achieved when proper boundary conditions together with some specified slip/twin systems are considered in the con?tinuum micromechanics mainly containing twinning and shear banding. The present investi?gation suggests that for fcc metals with a low SFE, the mechanism of shear banding is the dominant contribution to the texture development at large deformations.