| 摘要 |
PROBLEM TO BE SOLVED: To provide a high strength steel sheet having excellent press formability, and to provide a method for producing the same. SOLUTION: The high strength steel sheet has a composition comprising, by mass, 0.001 to 0.25% C,≤2.0% Si, 0.01 to 3% Mn, 0.0010 to 0.1% P, 0.0010 to 0.05% S, 0.020 to 0.010% N and 0.01 to 2.0% Al, and further comprising one or more kinds selected from 0.001 to 0.5% Ti, 0.001 to 0.5% NB and 0.001 to 0.5% V in the ranges satisfying inequalities (1) and (2), and the balance iron with inevitable impurities, and in which the particles of multiple nitride or multiple carbonitride of Al, and at least one kind selected from Ti, Nb and V with a particle diameter of 2 to 10 nm are present at the density of 1×10<SP>10</SP>to 1×10<SP>15</SP>pieces/m<SP>3</SP>: in the case Ti/48+Nb/93+V/51-C/12<0, Al/27≥3.0×(N/14) (1), and, in the case Ti/48+Nb/93+V/51-C/12≥0, Al/27+(Ti/48+Nb/93+V/51-C/12)≥3.0×(N/14) (2). The production method for the same is provided. COPYRIGHT: (C)2007,JPO&INPIT
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