E-coating on anodized aluminum?

A. Hi Anuj. I've never heard of anyone who is doing it -- probably because electrocoating is done on conductive substrates, and once aluminum is anodized it is no longer conductive, so the process would be quite specialized.

It is hard to say whether it would improve performance over alternative treatment sequences without knowing in exactly what way improved performance is sought. Certainly the surface of anodized aluminum is harder and more wear-resistant than e-coat or raw aluminum without quite a bit of development work.
Luck & Regards,

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

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A. Hi Alok. Few things are actually impossible, but e-coating of anodized aluminum sounds to me like it has a double whammy going against it:
In the first place, anodizing is a poor pretreatment for organic coatings, and adhesion would be problematical.
Secondly, anodizing is an electrically insulating (non-conductive) coating and the principal behind e-coating is that you need a conductive surface that becomes insulative as the e-coating builds up. So I'd say, no, you can't do e-coating on anodized aluminum.

Regards,