Influence of Grain-Matrix Interaction Intensity and Lattice Rotation Definition on Predicted Residual Stresses and Textures

Formation of residual stresses and crystallographic textures during rolling have been studied using elasto-plastic deformation for polycrystalline material (Leffers-Wierzbanowski model). The rotation of grain crystal lattices is the basic mechanism of texture formation and anisotropic behavior of metals during plastic deformation. The classical definition of crystal lattice rotation leads in some cases to different texture predictions than the definition based on the orientation preservation of selected sample planes and/or directions (preservation condition). Also predicted residual stresses can be influenced by a choice of rotation definition. In the used deformation model of polycrystalline material, the intensity of grain-matrix interaction is described by the parameter L= aG, where G is shear modulus and a is elasto-plastic accommodation parameter. Model calculations have been done for different values of this parameter and for two definitions of lattice rotation. The predicted second order residual stresses and crystallographic textures for cold rolled ferrite steel are compared with experimental ones.