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PTFE impregnation of aluminum anodizing

2002

We are also looking for a PTFE-related process which complies to MIL-A-63576A (AR) Type I - the impregnation process on unsealed anodic coatings.

Please advise?

Alex Chong
- Singapore

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April , 2009

Hi, Alex. This specification is for a PTFE coating/impregnation on unsealed hardcoat anodizing. It was cancelled in 1998 and last revised in 1985, so it's getting rather dated.

But I don't see any Qualified Products List associated with it, which I believe would mean (unless it's there and I missed it), that you can use anything that works and allows the parts to comply with the rest of the specification.

Some of the experienced anodizers here have pointed out [see letters 1819] that PTFE particles are larger than the anodizing pores, such that it really isn't an "impregnation" process; further, the spec itself speaks of coating the "asperities" rather than impregnating the cavities.

A coating material was suggested in those referenced letters, and hopefully a reader will suggest additional alternatives. Good luck!

Regards,

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

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November 25, 2009

Hi! Alex,
Let in my knowledge, PTFE Impegration on anodized surface is a only one kind of sealing process which fills the cracks devloped during the anodizing process and gives the smooth surface with lubricity.

Thanks,

Tejas Badheka
- Ahmedabad,Gujarat, India