| 摘要 |
PROBLEM TO BE SOLVED: To provide a low yield ratio type high strength cold rolled steel sheet which exhibits excellent workability and shape fixability when subjected to working mainly bending. SOLUTION: The low yield ratio type high strength cold rolled steel sheet having excellent workability and shape fixability consists of steel with a composite structure comprising ferrite or bainite as a phase having the maximum volume fraction, and comprising martensite of≤25% in a volume fraction. The average value (A) of the X-ray random intensity ratios in the ä100}<011> to ä223}<110> orientation groups in the sheet face in at least 1/2 a sheet thickness is≥4.0. Also, the average value (B) of the X-ray random intensity ratios in the three crystal orientation of ä554}<225>, ä111}<112> and ä111}<110> is≥3.0. Further, 1.0≤(A)/(B)≤4.0 is satisfied. Additionally, at least one of r values in a rolling direction and in a direction perpendicular thereto is≤0.7, and the average value of the r values is≥0.8. COPYRIGHT: (C)2004,JPO
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