Galvanic corrosion potential is a comparison of how unlike metals will corrode when next to each other in an assembly. For galvanic corrosion to occur there needs to be an electrolyte present, usually water. The less noble material will corrode first if there is an electrolyte present.
This is a handy chart to compare galvanic corrosion potential with common materials. Zinc is on top of the list, which is commonly used as a sacrificial layer for corrosion on fasteners.
Key
= Galvanic action insignificant
= Galvanic action may occur
= Galvanic action will occur
To be used only as a guideline to compare materials for galvanic corrosion.
Download PDF to use as a reference.