Cold Rolled Steel Sheet

Abstract: This cold rolled steel sheet has a predetermined chemical composition, and a metal structure at a quarter depth position, which is a position at quarter of the sheet thickness from the surface of the sheet, comprising, in volume ratio: greater than 1.0% and less than 10.0% of retained austenite; at least 80.0% of tempered martensite; a total of 0-15.0%, inclusive, of ferrite and bainite; and 0%-3.0%, inclusive, of martensite. The average crystal grain size of the first crystal grains counted from the surface in the sheet thickness direction is at most 20.0 µm when viewed from a cross section parallel to the rolling direction and parallel to the sheet thickness direction, and is at most 30.0 µm when viewed in plan view of the surface.

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