| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for manufacturing a high-strength cold-rolled steel sheet, which stably manufactures the steel sheet without causing defects of a shape due to deformation on the outer surface during cooling, when manufacturing the high-strength cold-rolled steel sheet including a steel strip. SOLUTION: The method for manufacturing the high-strength cold-rolled steel sheet is characterized by quenching the steel sheet so that a maximum value of a differential coefficient determined by double-differentiating a temperature of the steel sheet during quenching at positions in a transportation direction can be a value of a differential coefficient corresponding to a predetermined maximum amount of tolerant curvature, or less, in a process for manufacturing the high-strength cold-rolled steel sheet by the use of a continuous annealing facility having a quenching means. The value of the differential coefficient is controlled preferably by carrying out at least one of the following actions (a) to (d): (a) adjusting the temperature of the cooling medium for quenching, (b) adjusting a starting temperature of quenching, (c) adjusting a transportation speed of the steel sheet in quenching, and (d) adjusting a coefficient of heat transfer of the cooling medium for quenching. COPYRIGHT: (C)2004,JPO
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