Patent ID: 6413329
Filing Date: 2002-07-02
Classification: C22C

Abstract:
A high strength forged steel for dies having excellent machinability, which consists essentially of, by weight, 0.005 to 0.1% C, from more than 0.05% to 1.5% Si, not more than 2.0% Mn, from 3.0 to less than 8.0% Cr, 1.0 to 4.0% Ni, 0.1 to 2.0% Al, 0.3 to 3.5% Cu, 0.1 to 1.0% Mo, and balance of Fe and unavoidable impurities including nitrogen and oxygen, and which has a metal structure whose primary microstructure is martensite and has a hardness of 35 to 45 HRC, and wherein an average packet size of the martensite is not greater than No. 8, and nitrogen and oxygen as impurities are restricted to amount ranges of not more than 0.02% nitrogen and not more than 0.003% oxygen.