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Problems and solutions for chromium plating of aluminum

I'd like know, about any problems for chromium plating on aluminum and what is the better alloy of aluminum for chromium plating.

Example:boiling

Completing the questions. What is the better sequence for chromium plating on aluminum .

Adriano Alibune
process supplier - São Bernardo do Campo, São Paulo, Brasil
2005

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Do you presently offer processes for chromium plating on aluminum, Adriano? If so, please describe the problem(s) you are having rather than asking us to coincidentally cover your problem by taking a scattergun approach and attempting to name every possible problem :-)

You probably already know that entire chrome plating books aren't fully successful at that, which may be why you are writing. Thanks.

Purer aluminums and the 6000 series like 6061 and 6063 are probably the easiest to plate. I'm guessing that you are asking about decorative nickel-chrome plating rather than hard chrome plating, and the usual sequence would be etch, desmut, zincate, strip, zincate, alkaline copper cyanide or electroless nickel, semi-bright nickel, bright nickel, chrome.

By 'boiling' you may have meant 'blistering'. This is usually caused by poor zincating or by inadequate copper thickness, but a hundred things can go wrong and the problem could well be something else entirely. The more info you can provide, the more help you can get.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2005

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Continuing with the questions about nickel-chrome plating in aluminium. Here in Brazil we have the sequence: soak cleaner, acid attack, zincate, strip(HNO3), zincate, electroless nickel, watts nickel, acid copper, nickel electroplating, chromium.

I'd like to know what the better time this sequence, only to preparation and what the better alloy to work.

Adriano Alibune
SurTec do Brasil - São Bernardo do Campo, São Paulo, Brasil
2005