| 摘要 |
<p>A Si-killed steel wire rod for obtaining a spring excellent in fatigue properties and a spring excellent in fatigue properties obtained from the steel wire rod are provided. The Si-killed steel wire rod of the present invention contains Sr: 0.03-20 ppm (means "mass ppm", hereinafter the same), Al: 1-30 ppm and Si: 0.2-4% (means "mass%", hereinafter the same) respectively, and contains Mg and/or Ca by a range of 0.5-30 ppm in total. Also, in the Si-killed steel wire rod of the present invention, oxide-based inclusions present in the wire rod contain SiO 2 : 30-90%, Al 2 O 3 : 2-50%, MgO: 35% or below (not inclusive of 0%), CaO: 50% or below (not inclusive of 0%), MnO: 20% or below (not inclusive of 0%) and SrO: 0.2-15% respectively, and total content of (CaO+MgO) is 3% or above. A spring excellent in fatigue properties can be obtained by forming the spring from such steel wire rod.</p> |
