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Ductile protective coatings. Aluminium deposition?

Hi.

I'm a student researching protective coatings. I am looking for a ductile coat, which will protect nearly pure iron from rusting. I want to avoid using nickel. I thought about using aluminium.

Is it possible to electrodeposit aluminium, and what salt do you use? what are the conditions? Is there any peculiarities I should know about?

Does anyone have suggestions of other possible coatings?

Thanks,

John Persaud
- Reading, Berkshire, UK.
2000

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Aluminum is a good choice for protecting iron -- probably better than nickel -- but the general method of deposition is by ion vapor (IVD). A number of job shops offer the process. I understand that electrodeposition of aluminum is not recommended, but that is outside my field of expertise.

Jim Treglio - scwineryreview.com
PVD Consultant & Wine Lover - San Diego,
California
2000

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Aluminum is too active to be electroplateable in the conventional sense. It is possible to do from organic solvents in a closed system, but my understanding is that there is only one shop in the world doing it. Other ways of applying aluminum are by vacuum metallization, Ivadizing, and hot dipping.

More conventional, unless you have reasons against it, would be to protect the iron with zinc, applied by hot dip galvanizing, mechanical plating, or electroplating.

The best ductile metal to protect the iron with is probably cadmium. But, because it is a cumulative poison, it is only used in very unusual circumstances today.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2000