Protective Coating 1

[roozle]

I need to determine the protective coating that is required by FAA or CAA, for aluminium parts located in aircraft interiors. Maybe Ali-Chrome coating or special yellow anodise??? Thanks for your answers.

Highest Regards,
Roozle

 

[WKTaylor]

roozle..

I have never heard of the materials You indicated.

The FAA does NOT specify corrosion protection as You were expecting: it is part of the damage protection scheme for structures and systems... and interiors MUST not contribute to structural or systems corrosion. This includes metallic protection schemes and use of non-corrosive non-metallic materials and other chemicals materials [such as fire-proofing impregnants]. These materials must NOT out-gas, cross-link or otherwise transfer corrosive chemistry [clorine, salts, etc]; or otherwise don't encourage corrosive behavior, such as trapping moisture against metal parts [IE: moisture-proof insulation].

Typically "Alodine" [AMS-C-5541] and Epoxy Primer [MIL-PRF-23377, or variations of this primer] are used for aluminum protection.

All non-metallic materials have to be checked for moisture retention, out-gas constiuents, contact chemistry [IE: materials touching sometime cross-link, like rubberbands against certain paints], abrasiveness, fire resistance... etc. This includes "new" and aged" versions of the same materials. Regards, Wil Taylor

 

[IRstuff]

Yellow is probably a chem-film.

TTFN

 

[roozle]

Yes the surface treatment is yellow. Do you have any more infomation regarding this.

Rgs,
Roozle...... Highest Regards,
Roozle

 

[WKTaylor]

roozle...

It's hard at best, impossible at worst, to diagnose coating-systems without hands-on inspections.

The surface is "yellow" could mean a host of things, based on Your perspective.

a. If this is an aluminum surface that appears to "shimmer" with a "golden-yellow" reflection-tone, it could be alodined or chromic acid anodized... or possibly phosphoric-acid anodized if viewed at an angle.

b. If this is a painted coating it could be an epoxy, polyurethane or enamel primer [in that order] with yellow corrosion-protective pigments... or if the assy is adhesive-bonded, it could be an adhesion promoting epoxy primer.

It could also have a + b on it.

More specific deatails are important. Regards, Wil Taylor