STEEL WIRE ROD FOR HIGH-STRENGTH SPRING EXCELLENT IN WIRE DRAWABILITY, MANUFACTURING METHOD THEREFOR, AND HIGH-STRENGTH SPRING

摘要

Provided are: a steel wire rod 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 rod material for a high-strength spring; a high-strength spring produced using the steel wire rod material for a high-strength spring as a material; and others. This steel wire rod material for a high-strength spring is a steel wire rod 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 size numbers and the standard deviation (Pσ) of the pearlite nodule size numbers fulfill the following formulae (1) and (2), respectively:; 9.5≦Pave≦12.0;  (1); and; 0.2≦Pσ≦0.7  (2).