Evaluation of combined hardening coefficients of zircaloy-4 sheets by simple shear test

Springback prediction in the simulation of multi-step stamping of zircaloy-4 metal sheets requires accurate understanding of the material behavior and in particular of the Bauschinger effect. In this study, issues concerning the one-sided simple shear test (specimen size, tightening torque and measurement of simple shear displacement) are discussed and suggestions regarding the test set-up are made. Forward/reverse simple shear tests are then performed with zircaloy-4 sheets to obtain shear load-displacement (P-delta) curves. In addition, applying the combined isotropic/kinematic hardening model the test is simulated in Abaqus/Explicit. Finally, the hardening coefficients for the combined isotropic/kinematic hardening model for zircaloy-4 sheets are determined by fitting the P-delta curve from finite element analysis (FEA) to the experimental curve. Applying the results to springback analysis will serve to improve the accuracy of multi-step stamping of zircaloy-4 sheets. (C) 2014 Elsevier Ltd. All rights reserved.