Conversion coatings on aluminum

Where do I find information about conversion coatings on aluminum. I want to replace the native oxide with a surface alloy or something else that is a better electronic conductor than the initial surface oxide so that I can electroplate onto aluminum foil

Any suggestions ?

Conductivity may not exactly be the question: it's possible to phosphoric acid anodize and then electroplate.

But the most conventional way of plating onto aluminum is to do a 'zincate' pretreatment, which consists of immersing the article in a highly caustic zinc-rich solution, stripping in nitric acid, and repeating. Look up 'zincate' in the guidebooks for further detail or inquire of Atotech regarding their proprietary alternative 'Alstan', or Canning-Gumm Chemical [now Macdermid] for their proprietary alternative 'Bondal'.

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

Chemicals solutions to produce chromate conversion coatings on aluminum are sold by a number of companies worldwide. One of these manufacturers is probably your best source for technical information. The US Dept. of Defense maintains a long list of products approved to meet the military specification (QPL-81706 [⇦ this spec on DLA]). Two of the most widely recognized are Alodine(R) by Parker Amchem [now Henkel] and Iridite(R) by Macdermid. In fact, these brand names are often used generically when referring to chemical conversion coatings.

Conversion coating on aluminum and plating on aluminum are two different things. Ted recommended a process for plating and Chris for conversion. They do not go together, if you apply a chromate film you cannot plate on it only paint it.