Steel Sheet

Abstract: The present invention provides a steel sheet that can provide excellent bendability and excellent quenching properties, and that, when used as a machine component, can provide excellent hydrogen embrittlement resistance. A steel sheet according to the present disclosure comprises, in terms of mass%, 0.50-0.90% C, 0.10-0.50% Si, 0.20-1.30% Mn, not more than 0.100% P, not more than 0.100% S, not more than 0.100% Al, 0.01-1.20% Cr, and not more than 0.0150% N. The total area ratio of ferrite and cementite particles is not less than 95%. The average particle size of the ferrite is not more than 20.0 µm. The average particle diameter of the cementite particles is not more than 1.50 µm. The spheroidization ratio of the cementite is not less than 85%. The C concentration ratio F1 defined by expression (1) below is not more than 0.50, where [C]s is the C content at a position at a depth of 50 µm in the sheet thickness direction from the surface of the steel sheet, and [C]c is the C content at the center position in the sheet thickness direction of the steel sheet. (1): F1=[C]s/[C]c

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