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Galvanic Corrosion between Gold Circuit Board and Aluminum

I plan to mount an immersion gold circuit board directly to an aluminum plate. I am concerned about the galvanic corrosion that may result. Critical to the application is maintaining the electrical contact between the metals. I am conversion coating (possibly Iridite) the aluminum (6061-T6), but when the board is screwed down, the thin layer will likely be penetrated allowing the gold to be in direct contact with the aluminum.

Are there any other suggestions for a solution, what degree of corrosion may occur, and is it even a concern considering it will be an indoors application with a life of ~10 yrs?

Doug Watson
- Austin, Texas
2001

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It is the aluminum, not the gold, which would sacrificially corrode. One piece of data we don't have here is the relative area of the aluminum and gold. If the aluminum plate is fairly large, so that the galvanic current is spread across a large area, the corrosive effect would be lowered.Considering the indoor environment, this doesn't sound like a big problem.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2001

Did you ever get an answer/test this solution? I have a similar problem where I need good electrical contact on a gold/nickel/brass pin press-fit into aluminum block.

Joel Kindem
- Poway, California, USA
2005