| 摘要 |
PROBLEM TO BE SOLVED: To provide a thin steel sheet for press molding, full in molding flexibility when press molding, reduced in defective fraction and capable of improving productivity, and to provide its production method. SOLUTION: This thin steel sheet for press molding, has a fineness number of ferrite of above 10, one or above of Nb type and Ti type deposits, and a low density area low in deposit density in grain boundary neighborhood, wherein this deposit density is below 60% of central part of ferrite grains. Further, the thin steel sheet has the range of the low density area of 0.2μm or above and below 2.4μm from grain boundary, BH amount of 10 MPa or below, and the chemical composition of 0.002-0.02% C, below 1% Si, below 3% Mn, below 0.1% P, below 0.02% S, 0.01-0.1% sol.Al, and 0.01-0.4% N, and can also contain one or more of below 0.0002% B, 0.01-0.4% Nb and 0.005-0.3% Ti.
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