alright so i was wondering if just 2 different metals are needed to form a galvanic cell ( with of couse the aqueous solutions)

If galvanized is involved, I could only assume it's coated with zinc.

So, impartially, yes.

for example, can silver form a galvanic cell with copper?
so all different metals can form a galvanic cell?

The propitiatory force behind galvanization is being coated with zinc.

By that definition, I would say no. But... I'm not an authority on the subject.

I don't think I can offer you much assistance without further research

oh okay, but from what i read it takes 2 different metals but that was from wiki so i wanted to get some support for it

It's called Galvanic after it's inventor, nothing to do with zinc. And yes, in theory any two metals can be used. In fact, you can even use the same metal as both a cathode and anode, as long as the ion concentration is different in each solution.
You can look up electrode potential for your two metals and figure out the total theoretical voltage output of your cell. Real output will be lower, of course.

What if your electrode potential is both positive and visa-versa

This post was edited by Rice_killer on Feb 27 2012 10:19pm

We are welding galvanized pipe, and it sucks!

Electrode potential is just in relation to hydrogen. There isn't really such a thing as "positive" or "negative", it only means that it's either stronger than hydrogen's or weaker. The difference between them will be your overall voltage. If both are positive or negative, your difference will simply be smaller than if one was positive, and the other negative.

this!