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Question on zinc-nickel plating

I would like some information on the percentage of nickel and its effects on effectiveness of zinc-nickel plating.

Pete Ruzicka
- Manlius, New York, USA
2001

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It depends on the proprietary bath you will be using.Very low percentages of nickel can have an enormous effect on the corrosion protection of the alloy. See individual Technical Bulletins from the chemistry suppliers.

  
Tom Pullizzi
Falls Township, Pennsylvania
2001

Up to 10% Ni in a Zn-Ni alloy plating would be advantageous in corrosion protection beyond which the plate becomes more noble than the substrate and hence is of no use as corrosion resistance layer.

Viney Chaddha
- Gurgaon, India
2001

A nickel content between 10 and 15% gives the best corrosion protection. Under 10 % , this protection dramatically drops. Above, the Zn-Ni layer becomes noble in reference to the most common steels.

Guy Heylen
Heusden-Zolder , Belgium
2001

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There is actually a bit of debate is the plating world on nickel alloy % in zinc-nickel plating. There are advantages and disadvantages of one range over another. I have seen Ni% range from 6 to 20%. The optimum range is not clear. I think it varies greatly on who's zinc-nickel chemistry you are using. Each chemical supplier has their own proprietary system that acts slightly differently. I suggest you take this subject up with your plating chemical supplier(s).

Tim Neveau
Rochester Hills, Michigan
2001