Most of the work rolls and intermediate rolls used for cold rolling are manufactured as forged steel. With this technology, it is possible to obtain rolls which have a fine microstructure, low inclusion content, excellent compactness as well as good mechanical properties. These characteristics are essential to withstand the rolling stresses whilst still guaranteeing a perfect surface condition of the rolled strip. As constraints prescribed by the technology of rolling mills and the quality level of rolled products continue to evolve, a new generation of rolls has been developed. They aim at further increasing campaign length while continuing to reduce sensitivity to rolling incidents. Moreover, they are expected to improve the wear resistance and the roughness retention. All these properties can only be reached with even more alloyed grades, called semi-HSS and HSS grades. These grades are characterised by a chemical composition with a high chromium, molybdenum and vanadium content as well as by a high tempering temperature. They are produced with the classical manufacturing procedure, the forging of monoblock ingots.
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