Investigation into tribology of cold strip rolling

The key factors which determine the friction as well as the surface quality of the rolled strip are the amount of oil which is entrapped in the roll bite and the roughness of strip and roll. In the present paper, the influence of the hydrodynamic and the roughness effect on the entrained film thickness and on the friction conditions in the roll gap have been examined theoretically and experimentally. For the experimental validation of the theoretical findings, rolling tests with thin aluminium sheets are carried out. The main parameters for the hydrodynamic effect, i.e. the rolling speed, base viscosity and yield stress, and the ones for the surface effect, i.e. the surface roughness and its orientation, have been systematically varied throughout the experiments.