| 摘要 |
PURPOSE:To prevent the deterioration of characteristics at high temp. and to improve the durability under severe states by increasing the content of Mo in a specified range in a rolling material having a specified compsn. of cast iron granular material. CONSTITUTION:At least the outer layer material of the hot rolling roll is formed by the granular alloy consisting of by weight 2.8-4.0 % C, 0.5-1.5% Si, 0.5-1.0% Mn, <=0.08% P, <=0.06% S, 3.0-5% Ni, 1.0-3.0% Cr, 1.5-5.0% Mo and the balance Fe. In such an alloy, Mo enters the base metal to increase its hardness and to improve a high temp. softening resistance, therefore, exfoliations of deposited cementite and graphite at high temp. are prevented and complex carbides of high hardness are formed. As a result, other effects of additives are maximized at high temp., wear resistance, rough surface resistance and accident preventing resistance at high temp. are improved. When the MO content is <1.5%, said effects are diminished, inversely when it is >5%, a white iron is apt to be generated and a crystallization of a graphite is prevented. |
