Steel base rolls have a carbon ratio ranging between 1,50 and 2,10% and are Cr-Ni-Mo-alloyed. Chemical analysis and specific heat treatments give the material the high mechanical properties typical of steel and the wear resistance distinctive of cast iron. Hardness is constant in the whole working layer. The structure is made up of pearlitic matrix and of small carbides. Graphitic steel rolls have abetter thermal conductivity thanks to the presence of graphite nodules.
Steel base rolls are used for roughing, preparing, pre-finishing and finishing stands, for light, medium and heavy sections where high mechanical properties are required in severe rolling conditions. Graphitic steel rolls are mainly suitable for environments with high thermal stress.