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Consistency of Anodizing Thickness

2006

Hi.
For electroplating, the deposits are thicker at the edges and thinner at recesses. Can the same be said for an anodized deposits?
Thanks

Vincent Yeung
New Crown - Hong Kong

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Hi Vincent. The general answer is no, anodized coatings do not tend to be thicker at the edges like electroplated coatings. This is why:

In both cases, the implications of Faraday's Law of Electrolysis apply, i.e., that the coating thickness in any area will be proportional to the current flow to that area. And in both cases the implications of Ohm's Law will apply, i.e., that the current will tend to take the path of least resistance. But the difference is that anodized coatings are highly insulative, which tends to drive the electricity away from the area where the coating is thickest and towards the area where the coating is thinnest, so the coating thickness will generally be fairly even.

But please tell us your situation rather than casting your question in the abstract, because a hundred ifs, ands, and buts can always apply and may bite you, but there is no way we can discuss every one of them. But if we knew your situation, we might know if one applied, and be able to warn you. Thanks!

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2006