A semi-empirical friction model for cold metal rolling

A semi-empirical model of friction is developed for cold metal rolling in t he mixed lubrication regime. An asperity flattening model is used to invest igate the evolution of the contact area and hydrodynamic pressure between t he roll and strip surface. An appropriate coefficient of friction for the c ontact areas between roll and strip surfaces is determined empirically usin g tests on a strip drawing rig. The asperity flattening model is combined w ith the empirical data for friction on the contact areas to predict the eff ect of speed on friction in rolling. Predicted values of friction coefficie nt are in reasonable agreement with published measurements.