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Ever heard of hard chrome plating aluminium, via anodizing?

April 20, 2009

Looking at some high volume plating, and seeing if anyone had a answer to this question.
Any help or ideas would help.

ever heard of Hard Chrome plating aluminium, via anodizing?

Thanks!

Klint Schuster
Sales - Tulsa, Oklahoma

Hi, Klint. If you plate hard chrome onto very hard steel, a coating of a few ten thousandths of an inch may be fine, whereas if you deposit it on softer steel, you may need ten times that thickness. If you plate it onto a soft material like aluminum, you risk it cracking like an eggshell if subjected to a substantial load.

But, yes, it can be done by starting with a zincate, then an electroless nickel layer, then the hard chrome. In "Hard Chromium Plating", Guffie says some aluminum castings can be plated directly after acid activation. Conventional anodizing does not sound like it fits into the scheme, though, because it is an electrically insulating layer which cannot be electroplated onto. As a research matter, little is impossible, and perhaps you could hard chrome plate over a thin boric acid anodize or phosphoric acid anodize; but for high volume you probably need to look at production-proven processes.

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
April , 2009