Patent ID: 9044807
Filing Date: 2015-06-02
Classification: B21B,B22D,B32B,C22C,Y10T

Abstract:
1. A centrifugally cast composite roll comprising an outer layer formed by a centrifugal casting method, and an inner layer made of ductile cast iron and integrally fused to said outer layer; said outer layer being made of an Fe-based alloy having a chemical composition comprising by mass at least 0.8-3.0% of Cr, 1.5-6.0% of Mo, and 1.8-5.5% of V, and a metal structure in which the area ratio of graphite is 0.3-10%; said inner layer comprising a roll body portion fused to said outer layer, and shaft portions integrally extending from both ends of said roll body portion; and the total amount of Cr, Mo and V being 0.15-2.0% by mass in end portions of both shaft portions, and the difference in the total amount of Cr, Mo and V between one shaft portion and the other shaft portion being 0.2% or more by mass.