| 摘要 |
PURPOSE: A high-strength steel sheet and a manufacturing method thereof are provided to apply the high-strength steel sheet to parts of a chassis structure requiring high-strength and superior deep drawability. CONSTITUTION: A method for manufacturing a high-strength hot-rolled steel sheet comprises the steps of: reheating a slab panel, which comprises C of 0.06-0.09wt.%, Si of 0.20-0.40wt.%, Mn of 1.30-1.50wt.%, Al of 0.15-0.25wt.%, Cr of 0.15-0.25wt.%, N of 60ppm or less, and Fe and inevitable impurities of the remaining amount(S110), hot rolling the reheated panel at an FDT(Finishing mill Delivery Temperature) 850-900°C(S120), cooling the hot-rolled panel(S130), and coiling the cooled panel(S140). [Reference numerals] (AA) Start; (BB) End; (S110) Slab reheating step; (S120) Hot rolling step; (S130) Cooling step; (S140) Winding step
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