Study of edge-cracking characteristics during thin-foil rolling of Cu-Fe-P strip

A three-dimensional (3D) strip profile model is proposed to improve the accuracy of predicting the profile of the as-rolled thin-foil strip. The contact and rolling pressure distributions at a 6-high mill are calculated numerically using the geometric structure and boundary conditions in the width direction. The rolling pressure distribution in the rolling direction is determined by Fleck’s model, and the as-rolled 3D strip profile is predicted using the pressures in the width and rolling directions. The rolling force in the width direction causes elastic deformation of the rolls, which induces uneven deformation at the strip edges. Strip failure frequently occurs in the cold rolling process because of increasing edge-cracking. The onset of edge-cracking is introduced using the ductile fracture criterion in continuous thin-foil rolling. The states of stresses in the deformation zone are calculated using the finite element (FE) method. Thin-foil rolling experiments are carried out, and the results are compared with those of the proposed 3D model and FE simulations to verify the precision of the 3D strip profile model.