| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a hot press member having excellent ductility which has TS of 1,960 to 2,130 MPa and El of about 8.0 to 10%; to provide a steel sheet for the hot press member; and to provide a method for producing the hot press member. Ž<P>SOLUTION: The hot press member having excellent ductility has a composition containing, by mass, 0.35 to 0.40% C, 0.05 to 2.0% Si, 0.5 to 3.0% Mn, ≤0.05% P, ≤0.05% S, 0.005 to 0.1% Al and ≤0.01% N, and the balance Fe with inevitable impurities, and has a microstructure where the area ratio of a martensitic phase occupied in the whole structure is 90 to 100%, and also, the average grain size of old austenitic grains is ≤8 μm. Ž<P>COPYRIGHT: (C)2010,JPO&INPIT Ž
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