STEEL WIRE MATERIAL FOR HIGH-STRENGTH SPRING WHICH HAS EXCELLENT WIRE-DRAWING PROPERTIES AND PROCESS FOR PRODUCTION THEREOF, AND HIGH-STRENGTH SPRING

摘要

Provided are: a steel wire material for a high-strength spring, which does not undergo the increase in deformation resistance arising from the increase in hardness and can exhibit good wire-drawing processability and the like even when a heat treatment, which deteriorates productivity, is eliminated or a simplified and rapid heat treatment is employed instead; a useful method for producing the steel wire material for a high-strength spring; a high-strength spring produced using the steel wire material for a high-strength spring as a material; and others. This steel wire material for a high-strength spring is a steel wire material that has been hot-rolled already, and has a texture having a specified chemical composition and mainly composed of pearlite, wherein the average value (Pave) of the pearlite nodule grain size numbers and the standard deviation (Ps) of the pearlite nodule grain size numbers fulfill the following formulae (1) and (2), respectively: (1) 9.5 = Pave = 12.0; and (2) 0.2 = Ps = 0.7.