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Compare dual ni and triple ni decorative chrome plating

February 15, 2009

please compare the below mentioned decorative chrome types:
1. triple ni layer ( semi bright ni, bright ni, ni powder layer,chrome layer)
2. dual ni layer (semi bright ni, bright ni,chrome layer)

also I read from the article below
https://www.pfonline.com/articles/080801.html
that, by using triple Ni layer method we can reduce the overall thickness of ni layer consumed compared to dual Ni layer.

so is the triple Ni layer equivalent to the corrosion resistance of dual ni coating. which is cheaper of the two coatings.

Rakesh Mahendiran
engineer trainee - Nashik, Maharashtra, India

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February 16, 2009

Hi, Rakesh. Duplex nickel has been the minimum standard for OEM work for many decades. It is a fine finish but it is certainly not the ultimate: if you look at OEM specs from a number of manufacturers you will find many references to triple layers and even more.

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

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February 18, 2009

Dear Mr.Mooney,
thanks for the reply.
which among the above mentioned two process is cheaper?
which is the best method to measure the corrosion resistance of decorative chrome coating?

Rakeshmahendiran
- Nashik, Maharashtra, India

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February 19, 2009

Hi, Rakesh. People never write articles / promo pieces that suggest that their proposed process cycle is more expensive, less corrosion resistant, or generally inferior to the conventional approach that they are trying to supplant :-)

So, I think the implications of that article are very clear, that the triple layer is better. But if you feel that this should be challenged, I think you need to write a letter to the editor of the periodical where it was printed. It wouldn't be fair to challenge the article in a different venue that the authors may not even be aware of. There are dozens of proprietary process cycles for high quality chrome plating and I don't think any one is obviously superior to every other one in every situation. People switch from brand X to brand Y and back every day. But, in general, progress seems to be moving toward more & thinner layers rather than towards fewer & thicker layers.

Only real exposure testing can reveal which process is most corrosion resistant though. Most of the accelerated tests have proven to give erroneous results for a number of reasons, including the fact that sulfur in the test medium corrupts the potentials between the nickel layers, when that is so important to the corrosion resistance. But Nickel and Chromium Plating [on Amazon affil links] by Dennis & Such seems to indicate their preference for CASS testing over the alternative test procedures. Good luck!

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey