A method for the production of steel strip or - sheet comprising strain-induced martensite

摘要

PROBLEM TO BE SOLVED: To provide a strain-induced martensitic steel having high hardness and high fatigue strength and a steel strip composed of the strain-induced martensitic steel.;SOLUTION: The strain-induced martensitic steel with high hardness and high fatigue strength has a composition which consists of, by mass, 0.01-0.10% C, ≤3.0% Si, 5.0-10.0% Mn, 1.0-12.0% Ni, 4-18% Cr, either or both of Mo and W in amounts within the range satisfying Mo+1/2W=0.1 to 4.0%, ≤5.0% (including 0%) Cu, ≤0.15% (including 0%) N, ≤0.10% Al, ≤0.005% O and the balance essentially Fe and in which the value of A represented by equation A=Ni+0.65Cr+0.98Mo+0.49W+1.05Mn+0.35Si+Cu+12.6(C+N) (where unadded elements among selective elements are figured as zero) is regulated to 13-27%. Further, this steel has a structure containing ≥30 vol.% martensitic phase in austenite after cold working.;COPYRIGHT: (C)2001,JPO