MODEL OF COLD-ROLLING OF THIN METAL SHEETS BETWEEN NONPARALLEL ROLLS

This paper presents a method of obtaining an approximate solution to t he velocity and stresses in the cold rolling of a thin metal strip whe n the roll gap is not parallel. The material is assumed to be rigid pl astic, and we assume coulombic friction between the roll surface and t he material. The solution is obtained by means of an asymptotic expans ion in the parameter delta, which is the ratio of the strip entrance t hickness to the length of the plastic region. The solution of the appr oximate equations at the order where the non-plane strain behavior is first encountered is obtained by means of polynomial approximations, a nd the resulting deviations in the velocity and stress components from their plane strain values are displayed