| 摘要 |
PROBLEM TO BE SOLVED: To provide a galvanized steel sheet excellent in both of a balance of strength-ductility and adhesion of plating even in the case Si and Mn are largely incorporated into a base material steel sheet (:ferrite), and to provide a method for producing the same galvanized steel sheet. SOLUTION: This galvanized steel sheet excellent in a balance of strength- ductility and adhesion of plating has a composition containing, expressed in terms of the ferrite average composition, by mass, 0.05 to 0.25% C, <=2.0% Si, 1.0 to 2.5% Mn and 0.005 to 0.10% Al, in which the concentration of C in the surface layer part of ferrite directly below the plated layer is <=0.02% and further this steel sheet has a ferritic structure containing a martensitic phase of a tempered martensitic phase and a fine martensitic phase of >=50% by fraction in total, and the balance ferritic phase and retained austenitic phase, and the production method uses the same galvanized steel sheet.
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