High strength hot-dip galvanized steel sheet, high strength alloyed hot dip galvanized steel sheet with less difference in strength between central part and end part in the plate width direction and excellent in bending workability, and a method for producing these

摘要

A high-strength hot-dip galvanized steel sheet with improved bending workability and reduced strength difference between a center part and end parts in the sheet width direction is provided. A method for manufacturing the high-strength hot-dip galvanized steel sheet is also provided. The hot-dip galvanized steel sheet has a hot-dip galvanizing layer on a surface of a base steel sheet containing: C, Mn, P, S, and Al; Ti and B in amounts satisfying expression (1): 0.005×[Mn]+0.02×[B]1/2+0.025≤[Ti]≤0.15; N; and Si as needed; the remainder being iron and unavoidable impurities. The base steel sheet has 50 area % or more of the martensite, 15-50 area % of the bainite, and 5 area % or less of the ferrite, with respect to the overall metallographic structure.