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Anodized Aluminum in Caustic Washes

I have a spray nozzle made of aluminum and finished with a grey anodize that I would like to use in a caustic wash. What would the caustic wash do to the anodize? Is there another type of coating or finish that I could put on my aluminum nozzle that would make it suitable to be used in a caustic wash?

Thanks!

Wai Leung
- Wheaton, Illinois, USA
2003

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Caustic will dissolve the anodized coating immediately, Wei. Caustic will then also dissolve the aluminum. If it absolutely must be aluminum, I suppose you could electroless nickel plate it, but I don't think that's a very good idea because the smallest scratch would cause the nozzle to dissolve. I think you need to make the nozzle out of a different material, perhaps steel or stainless steel.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2003