Influence of intergranular mechanical interactions on orientation stabilities during rolling of pure aluminum

Abstract

Taylor strain principles are widely accepted in current predominant crystallographic deformation theories and models for reaching the necessary stress and strain equilibria in polycrystalline metals. However, to date, these principles have obtained neither extensive experimental support nor sufficient theoretical explanation and understanding. Therefore, the validity and necessity of Taylor strain principles is questionable. The present work attempts to calculate the elastic energy of grains and their orientation stabilities after deformation, whereas the stress and strain equilibria are reached naturally, simply and reasonably based on the proposed reaction stress (RS) model without strain prescription. The RS model is modified by integrating normal RS in the transverse direction of rolling sheets into the model. The work hardening effect, which is represented by an effective dislocation distance, is connected with the engineering strength level of metals. Crystallographic rolling texture development in roughly elastic isotropic pure aluminum is simulated based on the modified RS model, whereas orientation positions and peak densities of main texture components, i.e., brass, copper and S texture, can be predicted accurately. RS σ12 commonly accumulates to a high level and features a strong influence on texture formation, whereas RS σ23 and σ31 hardly accumulate and can only promote random texture. Cube orientations can obtain certain stability under the effects of RSs including σ22. A portion of elastic strain energy remains around the grains. This phenomenon is orientation-dependent and connected to RSs during deformation. The grain stability induced by elastic strain energy may influence grain behavior in subsequent recovery or recrystallization.