"Bob McConnell" wrote
The major corrosion problems occur when you mate dissimilar metals.
Copper to aluminum is probably the worst in my experience. Here in the
states, we mixed copper and aluminum wiring in houses for a while in
the 60's and 70's, before AL wire was completely outlawed. There were
two fixes developed to control the corrosion. One was a special alloy
for all fittings, screws, clamps, etc. that might came in contact with
either or both metals. I still see electrical hardware marked CU/AL to
indicate it is made from that alloy. Then a paste was developed that
would prevent the oxidation from occuring. All points where both
metals came together were coated with it, before and after assembly.

There are other combinations, some of which have galvanic properties.
There are anti-seize and other pastes to deal with some of those.
Sometimes, all you need is a good silicon based lube, liberally
applied and wrapped with shrink wrap and electrical tape to keep the
rain out.

Bob McConnell
N2SPP

Hi Bob, a caution to anyone using silicone for any part of a grounding or
bonding connection: silicone is a dialectric, and is not appropriate for
anything other than an outer component of waterproofing - which I gather you
meant but might have confused some folks. The copper pastes (or alloy
mixtures) which you mentioned are the appropriate internal and external
coatings for electrical connections in lightning protection systems - which
any ground radial system is also providing. These are available at most
electrical supply companies.

73,
Jack Painter
Virginia Beach VA