A novel analytical model for prediction of rolling force in hot strip rolling based on tangent velocity field and MY criterion

Abstract

In order to accurately predict the rolling force in hot strip rolling process, a new tangent velocity and corresponding strain rate fields are proposed in this paper. Based on the proposed fields and the linear MY (mean yield) criterion, the plastic deformation power and shear power of rolled strip is calculated firstly, then the friction power is obtained by the co-line vector inner product method. Finally, the total power function is described by a mathematical expression. By minimizing the total power function, the analytical solution of rolling force can be obtained. By comparisons of the experimental data with the results predicted by the proposed analytical model, Sims model and А. И. Целиков model, it is found that the application of the proposed analytical model leads to a better solution to prediction of the rolling force, especially in the first stand. In addition, the rationality of proposed method has also been verified by the finite element method (FEM). Moreover, the effects of various rolling conditions such as reduction rate, friction factor and shape factor on rolling force, location of neutral plane and stress state coefficient are discussed.