| 摘要 |
PROBLEM TO BE SOLVED: To provide a high strength hot rolled steel sheet having reduced anisotropy in r value, having a tensile strength of≥780 MPa, and having workability, particularly in both the properties of deep drawability and stretch flange formability, and to provide its production method. SOLUTION: The high strength hot rolled steel sheet having reduced anisotropy in r value, having a tensile strength of≥780 MPa and having excellent workability comprises, by mass, 0.02 to 0.20% C, 0.1 to 0.8% Mo, 0.02 to 0.40% Ti and 0.0005 to 0.005% Zr, and having a substantially ferrite single phase structure, and in which carbides comprising Ti and Mo with a mean particle diameter of≤10 nm are precipitated. COPYRIGHT: (C)2006,JPO&NCIPI
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