HIGH STRENGTH STEEL FOR WELDING HAVING EXCELLENT CORROSION RESISTANCE AND MACHINABILITY AND METHOD FOR PRODUCING HIGH STRENGTH STEEL SHEET FOR WELDING

摘要

PROBLEM TO BE SOLVED: To provide high strength steel for welding having excellent corrosion resistance, and to provide a method for producing a high strength steel sheet for welding.;SOLUTION: The high strength steel for welding has a composition containing, by mass, 0.03 to 0.3% C, 0.01 to 1.0% Si, 0.1 to 3% Mn, ≤0.03% P, ≤0.01% S, 3 to 7% Cr, 0.1 to 2% Al and ≤0.02% N, and also selectively containing one or more kinds of metals selected from 0.01 to 5% Cu, 0.01 to 5% Ni, 0.005 to 1% Mo, 0.005 to 0.1% V, 0.005 to 0.050% Nb, 0.005 to 0..03% Ti, 0.0005 to 0.05% Ca, 0.0005 to 0.05% Mg and 0.001 to 0.1% rare earth metals, and containing components satisfying Tp value, expressed by expression, of ≥1,150 and also satisfying Tc value, expressed by the expression, of ≥600. Further, the steel ingot thereof is subjected to hot rolling, and is thereafter air-cooled, so that the high strength steel sheet for welding is obtained.;COPYRIGHT: (C)2005,JPO&NCIPI