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|1. (WO2017037827) STEEL SHEET|
|Applicants:||NIPPON STEEL & SUMITOMO METAL CORPORATION
A steel sheet has a specified chemical composition, and has a steel structure comprising, in area%, 20 to 95% of first martensite in which at least two iron carbide grains each having an equivalent circle diameter of 2 to 500 nm are contained in each lath, 15% or less of ferrite, 15% or less of retained austenite, and a remainder made up by bainite and/or second martensite in which less than 2 iron carbide grains each having an equivalent circle diameter of 2 to 500 nm are contained in each lath. The total areal fraction of ND//<111> direction grains and ND//<100> direction grains in the steel sheet is 40% or less. The content of solid solution C in the steel sheet is 0.44 ppm or more.