Experimental and Numerical Comparison of Constitutive Equations Describing Cooper Behavior in Moderate Strain Rate Using Wire Drawing Process

In this article the prediction accuracy of Johnson-Cook and Zerilli Armstrong constitutive equations in describing materials behavior in drawing process of copper wires in moderate strain rate condition were investigated. Wire drawing force was measured in different combinations of drawing speed and areal reductions using a load cell connected to the drawing die. Simulation of wire drawing process according to experimental test was done using Johnson Cook and Zerilli Armstrong constitutive equations. A VUHARD subroutine was developed to introduce the constitutive equations to finite element code and was called during the simulation. The drawing force was considered as a parameter to compare the simulation results with the experimental ones. Results showed that the simulation with Zerilli Armstrong equation has better correlation with experimental results comparing to the Johnson Cook equation, and in some circumstances, it completely fits on the experimental results. This shows the high accuracy of simulation and constitutive models.