A modified method for lateral spread in thin strip rolling

摘要

A railing method to increase the width of the metal would have advantages in multi-pass strip production, giving high productivity and control of texture or planar anisotropy. In conventional flat rolling, however, it is difficult to produce metal flow in the lateral direction. A new method for spread rolling has been proposed in the literature, in which several portions of strip width were rolled between a roll that has many circumferential grooves and a flat roll. In the present work, new modifications in roll profile and numbers of grooves are introduced. The advantages of the new modifications are evaluated through rolling of commercially pure aluminum strips. It was found that a strip of 70 mm wide and 1 mm thickness have been widened by up to 3.1 percent for a reduction of 35 percent. It was also found that the planar anisotropy decreases. A special purpose nonlinear finite element program has been developed to deal with continuous change of contact between the roll and the strip in each rolling pass. The calculated strain tensor was utilized to investigate the localized necking.