| 摘要 |
PROBLEM TO BE SOLVED: To provide a high strength hot rolled steel sheet provided with excellent stretch-flanging properties and ductility. SOLUTION: The high strength hot rolled steel sheet has tensile strength of >=500 N/mm2, and has a structure essentially consisting of bainitic ferrite and/or granular bainitic ferrite, in which the crystal faces in the 322} <113> orientation and 111} <123> orientation are orientated parallel to the sheet face, and their random ratios are respectively controlled to >=3.0. The steel sheet preferably has chemical components containing, by mass, 0.010 to 0.10% C, <=1.5% Si, <=2.0% Mn, <=0.01% P, <=0.001% S, 0.02 to 0.006% Al and 0.05 to 0.40% Ti, and the balance essentially Fe.
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