Process and performance improvement of hot dip zinc coating by dispersed nickel in the under layer

The addition of alloying elements like Mg, Al, Ni and Pb into galvanizing baths has been known to influence significantly hot-dipped galvanized coating. Zn–Ni-alloy-based coatings have high corrosion resistance, good adherence and unique physical as well as mechanical properties. In the present work, nickel was dispersed in the under layer of hot dip zinc coating. The hot dip zinc coating containing dispersed nickel in the under layer showed substantial improvement in physical as well as galvanic performance. The presence of nickel in the under layer was found to result in good adherence, less porosity and better hardness. The presence of nickel decreases the thickness of the coating and enhances the corrosion resistance character.