| 摘要 |
A high strength galvanized steel sheet having tensile strength of 590 MPa or more which is excellent in fatigue property in punching work, and a manufacturing method thereof are provided. The microstructure includes a ferrite phase having an average grain diameter of 15 mum or less and an area fraction of 60% or more and a martensite phase having an area fraction of 5 to 40%, and an amount of one or more kinds of oxide selected from a group consisting of Fe, Si, Mn, Al, P, Nb, and Ti generated on a surface layer portion of the steel sheet within 100 mum in a steel-sheet-side depth direction from a surface of a base steel sheet directly below a galvanized layer is less than 0.060 g/m2 per one-side surface of the steel sheet.
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