Simulation of Asymmetric Rolling of a Multilayer Composite under Various Friction Conditions

The contact interaction between a thin composite strip and rolls during rolling is studied in the case where the exit end is maintained in a horizontal position. The friction coefficient values required for a straight exit end in asymmetric rolling of a multilayer metallic material are determined. Asymmetric rolling of a five-layer composite is simulated for different friction coefficients on the rolls. The tool–workpiece interaction is described by the Amontons–Coulomb friction law, with the friction coefficient varying from 0.1 to 0.4. The results show that for a friction coefficient of 0.2 on both rolls, the exit end of the strip has minimum curvature, remaining almost straight. For this case, a stress-strain analysis is performed and the linear-velocity distribution across the strip in the rolling direction is investigated. It is shown that after passing through the deformation zone, all material points move with the same velocity far below the linear velocity of the lower roll, indicating a continuous slippage of the strip on the bottom surface of the roll.