The effect of scaling on interfacial friction in hot rolling of steels

Hot oxidation and hot rolling experiments were undertaken in order to investigate scale formation and its effect on the frictional conditions in the hot flat-rolling of steels. The effect of scale thickness on the coefficient of friction in the hot rolling of a low carbon and a microalloyed steels is examined. A model of scale growth is presented, predicting the magnitude of the scale index as well as the thickness of the scale as a function of the temperature and time. The coefficient of friction is inferred from a finite-element code as a match between the measured and calculated roll force, torque, and forward slip. It is shown that the coefficient of friction increases with decreasing scale thickness. The break-up of the scale and surface defects are discussed. (C) 1999 Elsevier Science S.A. All rights reserved.