The improvement of back-up rolls properties in terms of wear resistance is driven by the need of longer and longer rolling sessions aimed to increase productivity and reduce costs. Chemical composition effect on contact fatigue phenomena, bringing to the occurrence of macroscopic damages named spalling, have been studied and tested in laboratory. Moreover, the removal by grinding operations of damaged portion of rolls surface should be not sufficient to restore the initial performances of material. Experimental tests showed that a portion of material below the damaged one keeps memory of the last fatigue cycle, and has to be removed