| 摘要 |
PURPOSE: A high-strength hot rolled steel sheet and a manufacturing method thereof are provided to obtain improved hot rolling performance by preventing the formation of an oxide resulting from the reduction of Ti and Mn during a hot rolling process. CONSTITUTION: A method for manufacturing a high-strength hot rolled steel sheet comprises the steps of: reheating a slab panel, which comprises C of 0.0005-0.0030wt.%, Si of 0.03-0.2wt.%, Mn of 0.1-0.4wt.%, S of 0.005-0.01wt.%, P of 0.05-0.08wt.%, Al of 0.01-0.10wt.%, Ti of 0.01-0.02wt.%, Nb of 0.02-0.04wt.%, and Fe and inevitable impurities(S110), hot rolling the reheated panel at an FDT(Finishing mill Delivery Temperature) of Ar3 point to Ar3 point+100°C(S120), and cooling the hot-rolled panel to 400-600°C and coiling the panel(S130). [Reference numerals] (AA) Start; (BB) End; (S110) Slab reheating step; (S120) Hot rolling step; (S130) Cooling/coiling step
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