Integration of physically based models into FE analysis: Homogeneity of copper sheets under large plastic deformations

In this paper, an integration approach consists of implementation of true internal state variables constitutive model to finite element (FE) analysis is presented. From the approach, the deformation homogeneity during severe plastic deformation of sheet (SPD) is investigated. Since there is not any constitutive model for large deformation that based on appropriated physical assumptions, here a new constitutive model is proposed that is entirely based on metallurgical mechanisms. Also, in order to achieve accurate results with low computation time, a new approach for integration of the constitutive model to FE analysis is presented. By coupling the constitutive model and FE analysis, the homogeneity of hardness of severely deformed copper sheet by constrained groove pressing is investigated. A comparison between modeling results and experimental data shows an acceptable agreement. The results show that in contrast to the previous modeling work, increasing the pass number of the process causes to lower inhomogeneity of hardness in processed sheet. (C) 2009 Elsevier B.V. All rights reserved,