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Alodine electrical conductivity issue

 

I understand that Alodine is electrically conducted coating, which does not affect grounding. Is it true?

Lev J. Balanovsky
- Feasterville, Pennsylvania, USA

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Yes, a thin coat to Mil-C-5541class 3 is often used in grounding areas. See AMS-C-5541 [link is to spec at TechStreet] and there are some numbers for this.

Martin Trigg surface treatment shop Stroud, Glos, England

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Calling the chromate conversions "electrically conductive" is really a misnomer. The Class 3 coatings are so thin that when put under pressure, they short through and those shorts conduct, the coating is not in itself conductive.

The variables involved are both the thickness of the coating, and the surface finish of both mating surfaces. If you had a highly polished pair of surfaces, it would be difficult at best to cause the neseccary "punctures" through the surface thus allowing electrical conductivity. Conversely, extremely rough finishes would allow conductivity with very little pressure.

Bob Denney
avionics Tampa, Florida

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Hello,

I am trying to find value (number) for relative conductivity of alodined aluminum.

Andrey Gleener
- Port Moody, BC, Canada