| 摘要 |
<p>A spring steel wire rod containing Si abundantly and further containing Cr, Cu, and Ni is provided to improve the pickling performance of the spring steel wire rod outstandingly by suppressing the concentration of Cu and Ni on the wire rod surface, thereby remarkably reducing the difference between the concentration of Cu in the surface layer and the concentration of Cu in the steel. A spring steel wire rod comprises: 0.35 to 0.7% by mass of C; 1.5 to 2.50% by mass of Si; 0.05 to 1.0% by mass of Mn; 0.05 to 1.9% by mass of Cr; 0.05 to 0.7% by mass of Cu; 0.15 to 0.8% by mass of Ni; 0.02% by mass or less of P; and 0.02% by mass or less of S with the balance being Fe and inevitable impurities, wherein the ratio of Si to Cu (Si/Cu) is within the range of 4.0 or more, the difference between the concentration of Cu in the surface layer and the concentration of Cu in the steel is 0.50% or less and the difference between the concentration of Ni in the surface layer and the concentration of Ni in the steel is 1.00% or less, and the spring steel wire rod is manufactured by a manufacturing method comprising a descaling process performed by shower prior to the hot rolling process, and a hot rolling process including a finish rolling process performed while carrying out shower cooling. The spring steel wire rod further comprises at least one selected from the group consisting of: 0.07 to 0.4% by mass of V; 0.01 to 0.1% by mass of Ti; and 0.01 to 0.1% by mass of Nb.</p> |
