Exemplary embodiments of the present invention can provide a galvanization method for hot-rolled steel sheet, cold-rolled steel sheet, or plating sheet of various compositions, which can avoid nonplating defects by using an Ni preplating procedure.
For example, an exemplary galvanization method can be provided for pickled hot-rolled steel sheet or annealed cold-rolled steel sheet which is free from non-plating defects which includes cleaning the surface of the plating sheet, preplating it with Ni, rapidly heating the sheet in a nonoxidizing or reducing atmosphere to a sheet temperature of about 430 to 500° C. at a heating a rate of about 20° C./sec or more, and then hot dip plating the sheet in a galvanization bath.
The exemplary amount of Ni preplating can be determined based on the plate type and amount of Si in the sheet steel to produce a hot dip galvanization that is free from non-plating defects.