| 摘要 |
<p>PURPOSE: A quenched and tempered steel wire with superior characteristics of cold forging is provided in which new factors affecting on the cold heading characteristics of the steel wire are maintained in the specific range so that separate quenching and tempering heat treatments are not required after performing cold heading. CONSTITUTION: The quenched and tempered steel wire having superior cold heading characteristics comprises 0.1 to 0.5 wt.% of C, 1.0 wt.% or less of Si, 0.20 to 2.5 wt.% of Mn, 0.03 wt.% or less of P, 0.03 wt.% or less of S and a balance of Fe and inevitable impurities and has 30% or more of carbide spheroidizing coefficient as a steel wire that is quenched and tempered by 700 to 1,300 MPa of tensile strength, wherein one or more constituents selected from 0.05 to 2.0 wt.% of Cr, 0.05 to 1.5 wt.% of Mo and 0.0003 to 0.0050 wt.% of B are additionally added to the steel wire, and wherein the steel wire is obtained by drawing.</p> |
