| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for manufacturing a wire rod which has superior cold workability, no decarburized layer in the surface part, and a superior descaling property, n as hot-rolled state. SOLUTION: The method for manufacturing the wire rod comprises the steps of (1) heating a billet containing C, Si, Mn, S, Al, and N, to 900-1,200°C, (2) making a dwell time in 650-750°C of a material to be rolled during continuous rolling to be less than 60 seconds, and total area reduction to be 30% or more, (3) making the material to be rolled in an inlet side of a finishing mill line, to be 700-880°C, (4) making the rolled material in an outlet side of a finishing mill line, to be 850-950°C, (5) making the temperature of the finish rolled material to be higher than an Ms point but lower than 850°C, and the temperature of the rolled material before being wound to be 600-650°C, (6) making the temperature after recuperation of a wound non-concentric-circle-shaped coil to be 700°C or higher, and (7) making the temperature of the non-concentric-circle- shaped coil to be 650-750°C, and then cooling it down to 500°C at the cooling rate of 0.15-1°C/second. COPYRIGHT: (C)2003,JPO
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