Simulation of PLC-effects in Al6061/Al2O3 alloys

Interesting and less understood phenomenon of jerky flow - Portevin Le Chatelier effect (PLC) in polycrystals is studied on the mesoscopic level. Apart from kinetic considerations of the phenomenon, the influence of stress concentrations is considered as a driving force of localization phenomena. The model is based on the recently introduced relaxation element method (REM) which maintains an unambiguous connection between the stress drop in local volumes of solids with the plastic deformation in it in combination with the cellular automata method. REM allows to consider local sites of plastic deformation with the gradients of stresses and strains. Modelling of the underlying mesomechanical mechanisms of this phenomenon in polycrystals of Al6061/Al2O3 within the approach mentioned above results in the prediction of the PLC-bands self-organization. The results of the simulations are in very good agreement with observed ones in experiments.