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

摘要

A high-strength spring steel wire is provided which secures excellent hydrogen embrittlement resistance even when the adding amount of alloy elements is suppressed, and has 80 area% or more of tempered martensite and 1,900 MPa or more of the tensile strength, in which a predetermined chemical composition is satisfied, with C and Si satisfying the relation of the expression (1) below, with prior austenite grain size number being No. 10 or more, and with the hydrogen absorption amount being 14.0 ppm or more. 0.73 % ‰¤ C + Si / 8 ‰¤ 0.90 % where [C] and [Si] express the content (mass%) of C and Si respectively.