STEEL FOR MOLD FOR INJECTION PLASTIC AND THE METHOD FOR HEAT TREATMENT

摘要

steel for plastic injection mould consists of 0.05-0.3 wt.% C, 0.1- 1.0 wt.% Si, 0.2-2.5 wt.% Mn, 1.5-7.0 wt.% Ni, 0.1-3.0 wt.% Cr, 0.1- 2.0 wt.% Mo, 0.5-5.0 wt.% Al and balance Fe with the standard impurities including up to 0.02 wt.% S, up to 0.02 wt.% P, up to 0.01 wt.% N, up to 0.01 wt.% O and up to 0.05 wt.% H. A method for heat treating the steel comprises air cooling the forged steel treated to solution at 850-950 deg.C, quenching at 500-600 deg.C, and aging at 500-700 deg.C after second solution heat treatment.