I have been told that there are big problems with corrosion/oxidation with Alumnium in contact with Carbon.

I am sure this combination is fairly common on cats & windsurfers, Al beams & carbon hulls, Al rudder housing & carbon rudder, al mast foot & carbon mast.

Does anyone have any experience of this, would you expect to get problems with 6082-T6 anodised aluminium and carbon fibre.

Yes this happens with carbon and steel, and I'm sure it happens with alum as well, since Al is electrically conductive. The solution that the designer of the carbon boat I'm getting came up with, was to lay a small strip of glass over the place where the metal mounts to the mast/beam/hull. It provides a non-conductive buffer that isolates the electrolysis.

See document here. I couldn't find a galvanic table that listed carbon fiber though.

http://bosunsupplies.com/Corrosion.cfm

The contact between the rivets and carbon needs to be isolated as well. I think they use paste for that but I could be wrong in that.

WOuter

Hi Grob,

Any aluminum alloy will corrode when in contact with carbon fiber. If the aluminum and carbon are in air a non-conductive barrier should be used to insulate them. If they are immersed in seawater then the surfaces of both materials should be completely sealed from the water. The oxide layer on anodized parts is not sufficient to prevent corrosion since corrosion of the aluminum will begin anywhere the coating is missing (scratches, drilled holes etc.) Do not use aluminum blind rivets in carbon fiber reinforced parts anywhere. Aluminum and carbon are used together for marine applications - for seawater primary batteries, and aluminum air batteries.

In many aircraft that have an aluminum alloy primary structure boron fiber is used for fiber reinforced composite parts specifically to avoid corrosion. Boron fiber is expensive.

Here is a galvanic potential table that includes graphite:
http://www.eaa1000.av.org/technicl/corrosion/galvanic.htm

-colin pitts