| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for producing a thin steel sheet having excellent workability including stretch-flanging properties, having uniform mechanical properties and exhibiting an excellent sheet shape. SOLUTION: This method for producing a thin steel sheet comprises a step of subjecting a continuously cast slab containing, by mass, <=0.8% C to rough rolling, a stage of performing finish rolling at (the Ar3 transformation point -20) deg.C or higher, a step of rapidly cooling the same to 500 to 800 deg.C at >120 deg.C/sec and a step of coiling the steel at 400 to 750 deg.C. The continuously cast slab may be composed of steel containing <=0.8% C, <=2.5% Si and <=3.0% Mn or steel further containing one or more metals selected from Ti, Nb, V, Mo, Zr and Cr by.0.01 to 0.2% or steel containing one or more elements selected from Ca and B by <=0.005%. Moreover, it is possible that the content of C is controlled to >0.8 to 1.0%, and the finishing temperature is controlled to (the Acm transformation point -20) deg.C or higher.
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