| 摘要 |
Disclosed is a hot rolled steel sheet which contains C, Si, Mn, Al, Ti, N, and S. The C, Ti, N, and sulfur contents satisfy the following condition (1), and the Si and Mn contents satisfy the following condition (2): [C]−{[Ti]−(48/14)×[N]−(48/32)×[S]}/4≦̸0.01  (1) 0.20≦̸([Si]/[Mn])≦̸0.85  (2) in which the symbol [X] represents the content (percent by mass) of the element X, and the steel sheet has a microstructure having an area percentage of bainitic ferrite of 90% or more, an area percentage of martensite of 5% or less, and an area percentage of bainite of 5% or less, based on the area of an observed field. This steel sheet excels in properties demanded in press working, such as shape freezing ability, hole-expandability, and bendability, even though it has a high tensile strength of 980 MPa or more.
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