Rolling Speed and Strain Energy Density of Asymmetrical Rolling of Aluminum Strip

Abstract

This work is mainly an investigation of strip curvature caused by the work roll speed or work roll radius mismatch in the asymmetrical rolling process for an aluminum strip. At the same time, we analyze the variations in the temperature field and strain field, and use the method of speed mismatch of upper and lower work rolls to calibrate the deformation curvature caused by coolant condition mismatch in the hot rolling process. Finally, we will use the strain density theory to predict the possible initial fracture area in the strip. For completeness, all the boundary conditions of heat transfer which may be encountered in a realistic hot rolling process are taken into account, such as heat convection of the surrounding air and the cooling water, boiling phenomenon of cooling water and radiation heat loss. Based on the large deformationlarge strain theory, and by means of the updated Lagrangian formulation (ULF) and incremental theory, a coupled thermo-elastic-plastic analysis model for the hot rolling process is constructed. The flow stress of the material in this model is taken as a function of strain, strain rate and temperature. Finally, the numerical analysis method developed in this study is employed to analyze the changes in the aluminum strip's temperature and other changes during rolling. In addition, the average rolling force obtained from the simulation was compared with that from experiments at China Steel Co., and the model in this study was verified to be reasonable.