HOT-ROLLING OF AN ALUMINUM-ALLOY USING OIL WATER EMULSIONS/

The effects of the rolling speed, reduction and emulsion composition o n the roll separating forces, roll torques, forward slip and the surfa ces after hot rolling of commercially pure aluminum strips are studied . The roll separating forces, roll torques and forward slip are measur ed and compared with the predictions of two mathematical models, a fin ite element model and a one-dimensional technique. By matching the mea sured and calculated roll separating forces, roll torques and the forw ard slip, the coefficient of friction as a function of the process par ameters is obtained also. The coefficient of friction reduces when the rolling speed or the emulsion concentration is increased but it is no t strongly dependent on the reduction. At higher rolling velocities th e forward slip is negative, indicating that the lubricating regime app roaches hydrodynamic conditions. (C) 1997 Elsevier Science S.A.