When designing Aluminium enclosures (rack mounted units), I've previously used an Iridite NCP finish to ensure electrical conductivity between panels (i.e. no oxide). Does anyone have any papers or similar on whether this is in fact effective? EMC for Systems and Installations & EMC for Product Designers by Tim Williams seem to suggest so, but I don't see it being done by all engineers, which I'd expect so if it were effective.
This also led me to question something else that seems to be taken for granted. When using a gasket between two unfinished aluminium sheet metal parts, would the oxide coating which develops on the aluminium not prevent the conductivity between the aluminium and the gasket thereby rendering the gasket useless?
Please tell me if you think this belongs in a different stack site.