Deformation microstructures and textures in steels

Abstract

Experimental evidence concerning the evolution of textures and substructures during cold rolling of low–carbon steel is presented and reviewed with some reference to the importance of these during subsequent annealing. Attention is paid to the orientation dependence of microstructure and stored energy of deformation. These are considered in relation to the Taylor factors for grains of different orientations in homogeneous deformation, and to the occurrence of different types of heterogeneity. Certain grain–scale heterogeneities appear to be important in defining the textures, which can now be predicted with some success using so–called relaxed constraint models. Intragranular heterogeneities also play a role and these especially affect the variation in substructure between grains. The strain–rate sensitivity of flow stress is an important parameter, which, depending on its sign and magnitude, may cause either severe strain localization in shear bands or lead to very homogeneous deformation structures where the influence of crystal orientation almost disappears.