The inherent advantage of the steel and chill rolls respectively made way for something in between where one can get higher hardness and toughness with better roll-strength. Thus, here, the conventional composite rolls are produced by a special double-pour casting method in which two independent zones - a shell of highly alloyed iron & another a softer graphitic-grey iron core are achieved.

The hardest type of roll is one in which cementite is contained in a martensitic matrix.

In newly installed up-to-date mills, high speed and heavy reduction rolling is performed and the rolls of topmost quality combining high strength with good wear resistance and deep hardness penetrations are instantly required to meet the highest grade of surface finish on the rolled sheet.