HOT DIP Zn-Al-Mg BASED ALLOY PLATED STEEL HAVING EXCELLENT CORROSION RESISTANCE

摘要

PROBLEM TO BE SOLVED: To obtain hot dip Zn-Al-Mg based alloy plated steel which has high corrosion resistance even with a drenching method where steel formed into a prescribed shape is dipped into a hot dip plating bath. SOLUTION: In the plated steel, a plated layer having a composition containing, by mass, 0.005 to 30.0% Al and 0.5 to 10.0% Mg, and the balance substantially Zn is formed on the surface of base steel via an alloy layer consisting of one or two kinds selected from an Fe2 Al5 intermetallic compound and an FeAl3 intermetallic compound. A structure where the plated layer infiltrates into the gaps of the alloy layer, and one or two kinds selected from an Fe2 Al5 intermetallic compound, an FeAl3 intermetallic compound, an Fe-Zn based intermetallic compound and an Fe-Zn-Al based amorphous compound are dispersed therein is preferable.