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Non-Nickel based Dyed Anodize Sealing

I have a prime defense contractor customer who called up indicating that a new program they are working on forbids / bans the use of nickel. They have some parts which are black anodized and they want to know if there are alternatives to nickel acetate sealing. They are also prohibited from using hex chrome, thus sodium dichromate is out, and cobalt is also on the restricted list! What alternatives are out there to conventional nickel acetate? Are they as effective and easy to use?

Milt Stevenson, Jr.
- Syracuse, New York
2007

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First of three simultaneous responses --

Boiling DI water seal.

Bill Grayson
Metal Finishing - San Jose, California, USA
2007

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Second of three simultaneous responses --

You could try using simple demin/distilled water at 96 °C+ for 10+ minutes. It is something I have tried myself with reasonable success.

Brian Terry
Aerospace - Yeovil, Somerset, UK
2007

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Third of three simultaneous responses --

Our mutual friend, Ling Hao from the Grand Rapids branch of the AESF, wrote a perfect paper on sealing of anodize. It covered every type of sealing and how they actually worked. I think he could help with this question. I have sent you his email address in private.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2007

Thanks Ted for your suggestion to contact Ling Hao which I've done and he's already gotten back to me. Assuming that nickel and cobalt are out, he suggested a cerium salt and an electrolytic sealer both of which need R&D to perfect. Commercially, he wasn't aware of any proven product or technology for nickel or cobalt free sealing of dyed anodic coating.

Milt Stevenson, Jr
- Syracuse, New York
2007