WIRE ROD FOR HIGH STRENGTH STEEL WIRE HAVING EXCELLENT DUCTILITY, HIGH STRENGTH STEEL WIRE, AND METHOD FOR PRODUCING THE HIGH STRENGTH STEEL WIRE

摘要

PROBLEM TO BE SOLVED: To obtain a wire rod having excellent wire drawability, and to provide a steel wire using the same as the stock under high productivity in a high yield and at a low cost.;SOLUTION: The wire rod for a high strength steel wire having excellent ductility comprises components of, by mass, 0.95 to 1.30% C, 0.1 to 1.5% Si, 0.1 to 1.0% Mn, 0.1% Al, 0.1% Ti, 10 to 50 mass ppm N and 10 to 40 ppm O, and the balance Fe with impurities, wherein, the area ratio of a pearlitic structure is 97%, and the balance bainite, pseudo-pearlite, ferrite, grain boundary ferrite and pro-eutectoid cementite. The area ratio of the pro-eutectoid cementite in the region of 100 m of the radius in the central part of the wire rod is 0.5%, and also, the area ratio of the pro-eutectoid cementite in the region of a depth to 50 m from the surface layer of the wire rod is 0.5%.;COPYRIGHT: (C)2011,JPO&INPIT