METHOD FOR MANUFACTURING HOT-DIP ZN ALLOY-PLATED STEEL SHEET

摘要

A base steel sheet is immersed in a hot-dip Zn alloy plating bath containing Al or Mg to form a hot-dip Zn alloy plating layer on the surface of the base steel sheet. Subsequently, an aqueous solution containing at least one polyatomic ion selected from the group consisting of a polyatomic ion containing V5+, a polyatomic ion containing Si4+ and a polyatomic ion containing Cr6+ is brought into contact with the surface of the hot-dip alloy plating layer. The aqueous solution contains the polyatomic ion in an amount of 0.01g/L or more in terms of the content of at least one atom selected from the group consisting of V, Si and Cr.