Prediction of the effects of hardening and texture heterogeneities by finite element analysis based on the Taylor model

Abstract

The main objective of this study is to simulate deformation induced anisotropy during the upsetting of commercially available pure aluminum AA1050 after being processed by the equal channel angular extrusion (ECAE) process including the friction effect. A Taylor-type polycrystalline constitutive model was adopted to investigate the effects of texture evolution and deformation heterogeneity during the ECAE and upsetting. In order to save computation time, a decoupled analysis between the crystal plasticity model and finite element method for the multi-pass ECAE and a fully coupled analysis for the subsequent upsetting process were conducted. The rigid-viscoplastic finite element analysis of the ECAE was carried out to determine the history of velocity gradient during the ECAE process in order to identify the effects of the processing routes A and C on texture evolution. The calculated history was applied to the crystal plasticity model to obtain the crystallographic texture distribution. Then, a finite element analysis based on the Taylor model was conducted for prediction of the anisotropic behavior of the three-pass ECAEed specimens which was obtained by applying the ECAE of the aluminum alloy AA1050 with routes A and C, respectively. For this analysis, algorithms for the data transfer of Euler angles and hardness were developed and implemented into the program. The good agreement between the measured and simulated deformed shapes indicates that the proposed simulation technique with the data transfer algorithms can be used effectively to simulate deformation induced heterogeneity during the bulk forming process.