Effects of Deformation Microstructure Morphology on Recrystallization

Abstract It is shown that deformation of commercially pure aluminum by different processes, namely cold rolling and uniaxial compression to a strain of 1.9, leads to different recrystallization characteristics. The deformation microstructures and the microstructural evolution during isothermal annealing at 280 °C are characterized by electron back scattering diffraction (EBSD), and microstructural path modeling (MPM) is used to analyze the microstructural data. Even though the two types of samples are deformed to the same strain, clear recrystallization differences are observed. These are related mainly to the nucleation attributes and also the growth of grains during recrystallization is different in the two samples. It is discussed how the two deformed microstructure morphologies and distributions of crystallographic orientations lead to different spatial distributions of nucleation sites, as well as different nucleation and growth rates, and thus to different recrystallization kinetics and recrystallized microstructures. The work highlights how important local microstructural variations in the deformed state are for recrystallization. Additionally, this paper illustrates how the MPM methodology may be used to deduce key information about nucleation and growth.