Development of a mixed film lubrication model in cold rolling

A cold rolling model based on asperity flattening and von Mises homogenous deformation for mixed regime is developed. The variations of the yield stress with strain and strain rate are considered in this model. Reynolds accurate “second order” equation was used to obtain the hydrodynamic pressure of the lubricant film. A more accurate relation for the variation of the lubricant viscosity with pressure and temperature is considered. This model seems to be powerful and practical with less assumptions, it can be used at high rolling speed and converges quickly. The calculation results agree well with the literature as well as with the measured data from a rolling mill.