| 摘要 |
PROBLEM TO BE SOLVED: To improve the uniformity and the adhesion of coating film by applying the metallic compound containing Ni base compound and Fe base compound at specified quantities on the surface of a steel sheet. SOLUTION: The metallic compound quantities applied on the surface of the steel sheet are converted into the Ni quantity and the Fe quantity and regulated to 1-200 mg/m2, respectively. Further, the Ni and the Fe contents to the total metallic quantity of the metallic compound are desirable to be by wt.% of 20-80%, respectively. When the heating and annealing are executed under non-oxidizing atmosphere after coating such a metallic compound on the surface of the steel sheet, the solid solution on the surface of the steel sheet in this process is executed with the decomposition of the metallic compound and/or the reaction with the steel sheet. Thereafter, when the steel sheet is coated by dipping into the galvanizing bath containing at least 0.05-0.30% Al, Fe-Zn crystals (ζ(Zeta) phase) are finely and uniformly developed to obtain the galvanized steel sheet excellent in the uniformity and the adhesion of the film. Thereafter, if necessary, the galvannealing treatment can be applied.
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