| 摘要 |
PURPOSE:To obtain a roll durable in a long term use by constructing a roll by using a tough steel as a core material and using a material in which graphite content is continuously changed from the outside layer surface toward inside by area ratios within a specific range and integrally melting both materials. CONSTITUTION:A core and an outside layer are composed of a tough steel and a material containing graphite respectively and both the materials are integrally melted to form a composite roll. The outside layer contains 2.4-3.4% C, 2.0-3.4% Si, 0.5-1.5% Mn, <=0.1% P, <=0.08% S, 4.5-10% Ni, 5-10% Cr, and 0.4-2.0% Mo and graphite is crystallized in the structure and the graphite continuously changes in a range of 0.5-10% of area ratios from the outer layer surface toward inside. Thus, the roll durable in a long term use for variable applications is obtained. |
