A two-wavelength model of surface flattening in cold metal rolling with mixed lubrication

A new model of surface flattening is developed for cold metal rolling in th e mixed regime. Longitudinal surface roughness is modeled by two separate w avelengths. The new model follows the asperity crushing analysis of Sutclif fe (1999) for unlubricated rolling but additionally includes a hydrodynamic model to account for the effect of the lubricant. The effect of various pa rameters including speed, reduction in strip thickness, roughness wavelengt h and lubricant properties is examined. The results show similar behavior t o previous models of mixed lubrication, with a speed parameter Lambda(s) ha ving the most influence, and confirm the results for unlubricated rolling t hat the short wavelength components of the surface roughness persist more t han the long wavelength components. The predicted changes in roughness are in good agreement with experiments.