Steady-state plane-strain cold rolling of a strain-hardening material

Abstract

Knowledge of the roll force and torque and of the interfacial stresses is important for the design of rolling equipment and for analysing roll deformation. In this work, a model for the steady-state plane-strain cold rolling of a strain-hardening material is proposed which can predict the roll force and torque with reasonable engineering accuracy over the usual range of process variables. The model is able to simulate the neutral point with the help of Coulomb's law with constant coefficient of friction. The effects of various process variables (reduction ratio, roll-radius-to-work-thickness ratio and coefficient of friction) on the roll force and torque and on the interfacial stresses are also studied. Further, it is shown that if strain-hardening is neglected, these parameters are under-estimated to a significant degree. As the quality of the rolled product depends on the deformation pattern, the paper also investigates the effects of the process variables and strain-hardening on the deformation.