| 摘要 |
PROBLEM TO BE SOLVED: To provide a high strength dual-phase stainless steel sheet having excellent shape fixability by which the issue of shape fixability which has been an obstacle to wide application of high strength steel sheets can be solved and also to provide its manufacturing method. SOLUTION: The steel sheet is characterized in that: it has a composition consisting of, by mass, 0.001 to 0.200% C, 0.01 to 3.00% Si, 0.01 to 10.00% Mn, <0.050% P, 0.0001 to 0.0100% S, 11.0 to 30.0% Cr, 0.03 to 10.00% Ni, 0.001 to 0.300% N and the balance Fe with inevitable impurities; a percentage of austenite phase in a metallic structure at room temperature is 5 to <80% and the balance of the metallic structure is composed of ferrite phase or strain-induced martensite phase or unavoidable precipitate phase; the tensile strength is≥500 MPa; and an r-value in a direction parallel to rolling direction, r<SB>0</SB>, and an r-value in a direction perpendicular to rolling direction, r<SB>90</SB>, are≤0.5, respectively. The manufacturing method is characterized in that hot rolled plate annealing conditions and cold rolled sheet annealing conditions are specified, respectively. COPYRIGHT: (C)2009,JPO&INPIT
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