METHOD FOR HEAT-TREATING HIGH-SPEED STEEL SERIES CAST IRON MATERIAL CONTAINING GRAPHITE AND COMPOSITE ROLL

摘要

PURPOSE: To provide a heat treating method suitable for a high-speed steel series cast iron material and a composite roll in which the external layer is provided with the same cast iron material. ;CONSTITUTION: A high-speed steel series cast iron material having a chemical compsn. essentially contg., by weight, 1.8 to 3.6% C, 1.0 to 3.5% Si, 0.1 to 2.0% Mn, 0.5 to 10.0% Ni, 2.0 to 10% Cr, 0.1 to 10% Mo, 0.1 to 10% W and total 1.0 to 10% of one or two kinds of V and Nb, and the balance substantial Fe and contg. graphite or the external layer of a composite roll in which the external layer is formed of the same high-speed series cast iron material and the inside is provided with an internal layer constituted of iron steel is subjected to austenitizing heat treatment at 950 to 1150°C, is thereafter subjected to hardening heat treatment to 600°C at ≥200°C/hr cooling rate and is subsequently subjected to tempering heat treatment at 460 to 590°C. In this way, the improvement of its wear resistance can be attained.;COPYRIGHT: (C)1994,JPO