Development of super short interval multi-pass rolling technology for ultra fine-grained hot strip

A new SSMR process to produce ultra-fine-grained hot strip is introduced, featuring: closely spaced rolling stands, continuous high speed rolling with moderately large reductions rolling, rapid interpass cooling and rapid finish rolling cooling. An ultra-fine-grained CMn steel strip (1μm) is obtained with a 700 MPa yield stress. A proper choice of the work roll diameter and a careful control of the friction coefficient should make it possible to keep the rolling force at a level compatible with the design capacity of a conventional rolling mill.