Hot working die steel, its heat treatment method and hot working die

摘要

Hot working die steel, its heat treatment method and hot working die. The composition of hot worked die steel, in wt%, is 2-8% Cu, 0.8-6% Ni, Ni:Cu ≥ 0.4, 0-0.2% C, 0-3% Mo, 0-3% W, 0-0.2 % Nb, 0-0.8% Mn, 0-1% Cr, the balance being Fe and other alloying elements and impurities. A curing heat treatment is performed while maintaining a temperature of 400-550° C. for 0.1-96 hours. The present invention improves the service life and hardness of the material.