
plating, anodizing, & finishing Q&As since 1989
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Zinc-nickel plating on aluminum Q&A, Problems & Solutions

Zinc-Nickel plating on Aluminum
Q. Hello everyone I want to electroplate Zinc-Nickel on Aluminum for XRF research purpose. I have alkaline zinc nickel plating bath. Can anyone suggest how I can do this plating successfully with good adhesion on Aluminum.
ABHISHEK KALIA- New Delhi
June 8, 2023
Aluminum How-To
"Chromating - Anodizing - Hardcoating"
by Robert Probert
There's a better chance of winning the lottery than of not liking this book. Finishing.com has sold 862 copies without a single return request :-)
A. Hi Abhishek.
Aluminum requires the proper pretreatment steps for aluminum (alkaline cleaning, alkaline etch, and desmut), followed by a zincating step, followed by a compatible 1st plating step, followed by the plating step of your choice.
Compatible first plating steps include either cyanide copper or alkaline electroless nickel plating.
Robert Probert describes in his "Aluminum How To" book →
a method whereby, since alkaline zinc and alkaline zinc-nickel baths are quite similar in composition to zincate baths, it may be possible to simplify the process -- using the alkaline zinc-nickel bath without electricity for the zincate step, and then skipping the cyanide copper or electroless nickel, and applying the current to deposit the alkaline zinc-nickel plating.
Luck & Regards,
Ted Mooney, P.E. RET
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
↓ Closely related postings, oldest first ↓
Q. I am seeking information about zinc-nickel vs zinc-cobalt plating. What are the pros and cons of each when plated on cast aluminum. we are trying to phase out cadmium plating.
Another item I need info. on is that after product is plated with one of the two, what type of corrosion protection film that will be conductive when colored black.
- Miami, Florida
2000
A. Are you presently using a black finish on your Cadmium? What is the application, what kind of part, and where is it used?


Tom Pullizzi
Falls Township, Pennsylvania
A. I have read your question several times and wish to offer the following information. I have had experience with folks like yourself who wish to get rid of Cadmium.
Zinc/Nickel is far superior to Zinc/Cobalt with regard to Corrosion Resistance. My suggestion would be to prepare the aluminum casting and put a layer of Electroless Nickel on it. (Thickness to be determined by your needs). After this, plate a layer of 8-10 microns of Alkaline Zinc/Nickel followed by an iridescent chromate film. I have seen such a coating that surpassed 5000 hours to corrosion of the aluminum. Any follow up questions will be responded to.


Ed Budman [dec]
- Pennsylvania
With deep sadness we advise that our good friend Ed passed away Nov. 24, 2018
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