Method for manufacturing steel sheet

Abstract

A method for manufacturing a steel sheet, including annealing a steel raw material having an Si content of 1.0 mass % or more and a Cr content of 1 mass % or less, under a condition satisfying: a following formula 1A if the Cr content of the steel raw material is 0.2 mass % or more and 0.6 mass % or less: 0.19 ≤ exp ⁡ ( - 10770 T + 273 ) * t ≤ 0.75 Cr [ % ] + 0.48 Formula ⁢ 1 ⁢ A a following formula 1B if the Cr content of the steel raw material is less than 0.2 mass %: 0.19 ≤ exp ⁡ ( - 10770 T + 273 ) * t ≤ 0.63 Formula ⁢ 1 ⁢ B or a following formula 1C if the Cr content of the steel raw material is more than 0.6 mass % and 1.0 mass % or less: 0.19 ≤ exp ⁡ ( - 10770 T + 273 ) * t ≤ 0.93 Formula ⁢ 1 ⁢ C where in the formulas 1A, 1B, and 1C, T is 500° C. or higher and a soaking temperature (° C.) during annealing, t is a soaking time (seconds) during annealing, and Cr [%] is the Cr content (mass %) of the steel raw material.

Dependencies are inferred from the claim text.