Finite-element analysis of severe plastic deformation in differential-speed rolling

Variations of speeds of the upper and lower surfaces of the sheet in the single-pass DSR are compared with those in the double-pass DSR. In the latter, a great portion of the power provided by the fast-speed roll was wasted through friction due to a large discrepancy in speed between the roll and the sheet. The fast-roll speed should have been lowered to 9.5 mm/s to avoid such a waste. Compared to the former, the average and the deviation of the effective strain through thickness in the latter were reduced from 3.55 to 3.35 and from 0.3 to 0.1, respectively.