SPRING STEEL WIRE ROD HAVING EXCELLENT WIRE DRAWABILITY AND EXCELLENT FATIGUE CHARACTERISTICS AFTER WIRE DRAWING, AND SPRING STEEL WIRE HAVING EXCELLENT FATIGUE CHARACTERISTICS AND EXCELLENT SPRING FORMABILITY

摘要

This spring steel wire rod having excellent wire drawability and excellent fatigue characteristics after wire drawing and this spring steel wire having excellent fatigue characteristics and excellent spring formability are characterized by containing 0.50% or more but less than 0.70% of C, 1.0-2.5% of Si, 0.50-1.50% of Mn, 0.5% or less of Cr (including 0%), 0.0010-0.0050% of B, 0.005% or less of N (excluding 0%), 0.020% or less of P (excluding 0%), 0.020% or less of S (excluding 0%), 0.03% or less of Al (excluding 0%) and 0.0020% or less of O (excluding 0%), with the balance made up of iron an unavoidable impurities, and are characterized in that the area ratio of the pearlite structure in the entire structure is 85% or more.