Aluminum Bar Plating

Have you looked into Aluchrome?

http://www.finishing.com/377/74.shtml

You'll need some intermediate plating for proper adhesion. Either nickel/copper, or just copper, I'm not sure.

Milo probablt could tell us.

I have a recollection from way back that copper on aluminium has a reaction that continues over a long period of time, gradually degrading. This comes from a company I worked for long ago that used extruded aluminium grilles, sometimes these were chrome plated with a copper underlay. They only gave a 2 year warranty on these because the chrome would start to bubble soon after.

I've pulled this from the deeper recesses of my memory which have also degraded over time so feel free to disagree.

We used to silver plate a lot of machined Al parts for various spacecraft electronics modules. I wasn't the plater. I don't remember the process well enough to contribute more without doing some research.

Agree with lyn, a barrier coat of Cu is indicated.

Also agree with lyn, Milo is a larger authority.

Aluminium is difficult to plate because it always has an insulating layer of oxide.

It is possible to "solder" it, and you may be able to solder areas and wipe them to leave tinned areas.

soldering aluminum search

There is a method, that always works.

That is vacuum ion implantation. Since the implantation depth is set by the accelerating high voltage, it punches thru a thin oxide film and builds up from the bulk metal. Once the "friendlier" metal is on the surface, sputtering or galvanizing is straightforward.

Obviously, galvanic corrosion protection is an issue from then on.

Do you realy need this method??

There are special compounds for aluminium to aluminium contacts, I have used these and it compleatly prevents corrosian between surfaces.

Here is a link to advise you; http://www.gvk.com.au/pdf/electrical_jointing.pdf

Aluminium bus bars aren't plated.

Scratch cleaning and immediate use of a corrosion inhibitor is standard practice.

Alminox is the go.

Aluminum bus bars are commonly used in many mobile high power electrical systems. Aluminum provides superior conductivity per unit weight. Aluminum bus bars are generally not plated. They are normally cleaned chemically or mechanically, a conductive compound placed between them and the bars are then tightly bolted together. A commonly used conductive compound is Penetrox made by Burndy. It is available in a petroleum or synthetic base. Be careful to follow bolting instructions if the connections are exposed to wide temperature swings.

A few years ago I had similar problems connecting Al busbars to copper connections. The solution was to get the ends of the Al busbars copper plated by plasma spraying them. The result was a very good Al to Copper interface. I don't know of the long term results but after ~ 2years the test pieces had not changed their joint charactoristics in any measurable amount.

Regards Bob