As a material for automobile parts, it has excellent fatigue resistance characteristics, TS 1180 ㎫ or more thin steel sheet and its manufacturing method, plated steel sheet plated with the thin steel sheet, manufacturing method of hot rolled steel sheet required to obtain the thin steel sheet, cold rolled full hard It is an object to provide a manufacturing method of a steel sheet and a manufacturing method of a plated steel sheet. In mass%, C: 0.08% or more and 0.3% or less, Si: 1.0% or less, Mn: 2.0% or more and 3.5% or less, P: 0.1% or less, S: 0.01% or less, Al: 0.01% or more, 0.1% or less, N : The component composition containing 0.015% or less, the balance being Fe and inevitable impurities, and the area ratio of the entire steel sheet, the area ratio of martensite is 50% or more and 90% or less, and the area ratio of ferrite and bainite The total is 10 to 50%, and the average solid solution Mn concentration in the ferrite in the region from the surface of the iron core to the depth of 0.5 µm is 60% or more of the average solid solution Mn concentration in the ferrite at a quarter of the plate thickness. A thin steel plate.
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