STEEL FOR LARGE SCALE PLASTIC INJECTION MOLD HAVING SUPERIOR HIGH TEMPERATURE STABILITY

摘要

PURPOSE: A steel for a large scale plastic injection mold having superior high temperature stability is provided to improve ordinary temperature/ high temperature strength properties and corrosion resistance by adding the small amount of V and Mo to alloy constituents of a mold material along the increase of the amount of Cr, decrease the deviation of the profile hardness and obtain homogeneous structure of the mold material by adding B, Al and N in a proper ratio, and improve repairing weldability by lowering the content of C. CONSTITUTION: The steel for a large scale plastic injection mold comprises 0.10 to 0.30 wt.% of C, 0.10 to 0.35 wt.% of Si, 0.85 to 1.30 wt.% of Mn, 0.20 to 0.50 wt.% of Ni, 1.5 to 2.3 wt.% of Cr, 0.30 to 0.50 wt.% of Mo, 0.08 wt.% or less of V, 0.0005 to 0.008 wt.% of B, 0.03 to 0.08 wt.% of Al, 0.002 to 0.01 wt.% of N, 0.025 wt.% or less of P, 0.015 wt.% or less of S, 0.005 wt.% or less of O and a balance of Fe and a small amount of impurities.