MILD STEEL WIRE ROD HAVING EXCELLENT ANNEALING CHARACTERISTIC, AND ITS PRODUCTION

摘要

PROBLEM TO BE SOLVED: To prevent a rise in annealing temp., which becomes a problem when a material of mild steel wire is used, and to obtain a wire rod having stable annealing characteristics and excellent in wire drawability by specifying respective contents of C and Ti in a steel and precipitating specific percentages of Ti precipitates in a wire rod in the form of Ti₄C₂S₂. ;SOLUTION: A steel, having a composition containing, by weight, ≤0.01% C and Ti in the amount satisfying 2≤Ti/C≤30, is cast continuously into bloom. It is preferable to form Ti into perfect solid-solution state at this time. This cast bloom is heated at 1000-1500°C to precipitate Ti, in the state of solid- solution, in the form of Ti₄C₂S₂ and hot-rolled into billet. Preferred temp. at hot rolling is ≥1000°C. Then, this billet is heated in a wire rod working furnace and formed into wire rod by means of a wire-rod mill. By this method, the desired wire rod, in which ≥60% of Ti precipitates contained in the wire rod are precipitated in the form of Ti₄C₂S₂ and tensile strength is regulated to ≤300MPa, can be obtained.;COPYRIGHT: (C)1998,JPO