Re: [VAL] galvanized aluminum

["Tom Patterson" <pattersontj@xxxxxxxxxxxxx>]

I suspect that they are referring to anodized aluminum.

-Tom

> Galvanized aluminum? Never heard of such a thing. Generally aluminum is
> weathers better than zinc. Zinc is coated onto steel as a sacrificial
> surface that protects the steel, even when scratched because the zinc
> corrodes preferentially to thee steel. Aluminum automatically makes its
> own protection with a coat of aluminum oxide.
>
> Perhaps you mean ALCLAD where the surface has a layer of pure aluminum
> with a core of stronger aluminum alloy. Airstream skins are made that
> way which makes them polish better than if the alloy was out to the
> surface and the pure aluminum stands up to the environment significantly
> better than the alloy.
>
> In wet environments, metals with inclusions like alloying elements will
> corrode more rapidly at the inclusions because of the shorted wet cell
> effect. When zinc is on steel, the zinc is eaten protecting the steel.