The tool steel null C which is superior in brief due to electrification heating or high frequency induction heating

摘要

PROBLEM TO BE SOLVED: To produce tool steel capable of realizing the hardness of ≥64 HRC after tempering even in hardening in a short time of ≤20 sec applied with high-frequency induction heating. ;SOLUTION: In this tool steel excellent in short time hardenability is composed of, by weight, 0.5 to 1.2% C, 0.05 to 1.0% Si, 0.10 to 1.00% Mn, 3.50 to 7.00% Cr, 4.00 to 10.00% Mo, 5.00 to 20.00% W and 0.80 to 2.00% V, and the balance Fe with inevitable impurities, V/W equivalent is controlled to 0.1, the quantity of carbides after annealing is 10 to 25%, and also, the occupancy ratio of carbides of ≤1.0 μm grain size among the above carbides is ≥60%.;COPYRIGHT: (C)2000,JPO