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Hard Anodising of high silicon content aluminum alloys

1996

I need to put a thick oxide layer ( more than 30 microns ) when hard anodising high silicon content ( over 10%) aluminum alloys .
These alloys are used by the foundries . Typically in the US it would be a 390 alloy .

Has anybody an idea of how to do that ?

All the tests we have done so far have resulted in an oxide layer thickness under 10 microns .

Thanks for your input .

Eric LABORDE - France

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The devil is in the details, Eric, but in general the way you get thick hard coatings, is to keep the temperature way down (25-32 °F. / -4 to 0 °F.), and apply high voltages (50 or more volts is not uncommon). But that is a great deal of silicon and certainly sounds like a problem :-(

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

You need a specialty chemistry hardcoat system for high copper alloys

David A. Kraft
- Long Island City, New York
1996