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How do you sulfuric anodize?

I need requirements for sulfuric acid anodizing, times, temps, concentrations, soft and hard for aluminum, any information would be appreciated

Steve Adams
Metalcraft technologies - cedar city
2000

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There is so much more to it than just the sulfuric acid anodizing tank itself that I think you may be misled if your questions are simply answered. First there is the issue of alloy and whether the item is wrought or cast; some anodize well, some poorly, and some almost not at all. Then the mechanical prep. Then the non-etch cleaner, the etch process, and the desmut before the anodizing. After anodizing is the rinsing, perhaps including bicarbonate neutralization or dilute nitric wetting, then the dyeing, the sealing, and the final rinsing.

letters #946 and #1148 will answer most of your questions about the sulfuric acid anodizing step proper.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2000