Mechanical Properties Volues Hardness of roll surface HSD55-65 Hardness of roll neck HSD35-50 Tensile strength of core ≥400MPa Chemical composition% C Si Mn Ni Cr Mo 0.4～0.7 0.2～0.6 0.7～1.2 0.1～1.0 0.8～5.0 0.2～0.8