| 摘要 |
PURPOSE: A high-carbon steel wire rod is provided which has superior drawability and good resistance to breakage and contributes to prolonged die life, and a method for production of the high-carbon steel wire rod is provided. CONSTITUTION: The high-carbon steel wire rod with superior drawability which has the chemical composition (in mass%) comprising 0.6 - 1.0% of C, 0.1 - 1.5% of Si, 0.3 - 0.9% of Mn, no more than 0.02% of P, no more than 0.03% of S and no more than 0.005% of N with the remainder being Fe and inevitable impurities, and the structure which is characterized in that pearlite accounts for no less than 95 area% and pearlite has an average nodule diameter (P) no larger than 30 μm and an average lamella space (S) no smaller than 100 nm such that the value of F calculated by the formula below is larger than zero: F = 350.3/(S¬1/2) + 130.3/(P¬1/2) - 51.7. The method for producing the high-carbon steel wire rod comprises the steps of hot-rolling with a finish temperature of 1,050-800 deg.C, cooling immediately the hot-rolled rod to a temperature of 950-750 deg.C at a cooling rate no smaller than 50 deg.C/sec, cooling further the rod to a temperature of 620-680 deg.C at a cooling rate of 5-20 deg.C/sec, and cooling the rod for no less than 20 seconds at a cooling rate no larger than 2 deg.C/sec.
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