Patent ID: 11224907

Abstract:
A composite roll for rolling having a structure comprising centrifugally cast outer and intermediate layers of an Fe-based alloy integrally fused to an inner layer of ductile cast iron; the outer layer having a composition comprising by mass 1-3% of C, 0.3-3% of Si, 0.1-3% of Mn, 0.5-5% of Ni, 1-7% of Cr, 2.2-8% of Mo, 4-7% of V, 0.005-0.15% of N, and 0.05-0.2% of B, the balance being Fe and inevitable impurities; the intermediate layer containing 0.025-0.15% by mass of B; the B content in the intermediate layer being 40-80% of that in the outer layer; and the total amount of Cr, Mo, V, Nb and W in the intermediate layer being 40-90% of that in the outer layer.