A hybrid model on severe plastic deformation of copper

A hybrid model based on the flow function and dislocation cell structure model by considering the Taylor assumption is utilized to model the dislocation structure evolution, cell size and mechanical properties of OFHC in severe plastic deformation. Here, the ECAP is chosen as a process of severe plastic deformation. In this study, the model is modified by taking the value of cell size coefficient as a function of strain and considering two different values of dynamic recovery coefficients of cell walls and cell interiors. These modifications lead to achieve the more accurate modeling results. From the flow function the strain rate distribution are achieved and then using the model the dislocation density, cell walls thickness, walls fraction, cell size, and strength are predicted. The predicted cell size and strength are compared with the experimental data and a remarkable agreement is obtained. (C) 2008 Elsevier B.V. All rights reserved.