Study of the corrosion properties of zinc-nickel alloy electrodeposits before and after chromating

In this study, corrosion behavior of zinc-nickel alloy electrodeposits on steel sheets has been investigated using the neutral salt spray test. The performance of the coatings with various nickel contents (up to 28 wt.%) was compared with electrodeposited zinc coating. The results show that the corrosion resistance of zinc-nickel alloy coatings is superior to that of pure zinc coating and the zinc-13 wt.% nickel gives the best protection. The corrosion behavior of chromated zinc-nickel alloy coatings was also studied. The results show that chromate conversion coating increases the corrosion resistance significantly (up to 3-4 times), and the best corrosion resistance is achieved by chromating of zinc-13 wt.% nickel alloy coating. (C) 2003 Elsevier Science B.V. All rights reserved.