STEEL WIRE FOR SPRING HAVING EXCEPTIONAL SPRING COILING PROPERTIES, AND METHOD FOR PRODUCING SAME

摘要

The present invention pertains to a steel wire for a spring having exceptional spring coiling properties and a method for producing the steel wire, characterized in that: the chemical components of the steel constituting the steel wire contain, in percent by mass, 0.1-1.5% of C, 0.01-3% of Cr, 1.0-2.5% of Si, and 0.01-2% of Mn, the balance being iron and unavoidable impurities; the contained amounts of each of P and S included in the unavoidable impurities are limited to more than 0% but no more than 0.05%; the steel wire has scale at a thickness of 1-5 μm on the surface thereof; and the constituent elements of the scale comprise, in percent by mass, 0.5-10% of Ca, 5% or less of the total of Si and Cr, and 10% or less of the total of C, Mn, P, S, Mo, Cu, Ni, Ti, V, Nb, and Zn, the balance being Fe and O.