PURPOSE: To obtain a one-side alloyed galvanized steel sheet having about equal amounts of metals stuck to the front and rear sides, by plating only one side of a steel sheet with Ni or Fe before passing the sheet through a reduction annealing stage prior to galvanization when the titled steel sheet for a car is manufactured.
CONSTITUTION: Only one side of a steel sheet is plated with ≥about 0.1g/m2 Fe or about 0.01g/m2 Ni, and the sheet is subjected to reduction annealing. The sheet is then dipped in a molten zinc bath, and after controlling the amount of zinc sticking to the sheet, alloying is carried out by heating to obtain a one- side alloyed galvanized steel sheet. The amount of the resulting Zn-Fe alloy sticking to the alloyed side (said plated side) of the steel sheet is 10W90g/m2, and the amount of zinc sticking to the unalloyed side is equal to or larger than said amount.
KOBAYASHI SHIGERU
IRIE TOSHIO
