HIGH-STRENGTH SPRING STEEL WIRE WITH EXCELLENT HYDROGEN EMBRITTLEMENT RESISTANCE MANUFACTURING PROCESS THEREFOR AND HIGH-STRENGTH SPRING

摘要

A steel wire for a high strength spring having a tempering martensite of 80% by area or more and a tensile strength of 1900 MPa or more, characterized by satisfying a predetermined chemical composition and satisfying the relationship of C and Si satisfying the following formula (1) A steel wire rod for high strength springs is provided that secures hydrogen embrittlement even when the addition amount of the alloy element is suppressed by making the number of particle diameters 10 times or more and the hydrogen occlusion amount to be 14.0 ppm or more. 0.73%? [C] + [Si] /8? 0.90% (One) Note that [C] and [Si] represent the content (mass%) of C and Si, respectively.