Galvanic Corrosion Table
What is a Galvanic Corrosion Table?
A
Galvanic Corrosion table is a table that
contains the galvanic series or electrochemical series
ranks of metals according to their potential, generally measured with respect
to the Standard Calomel Electrode (S.C.E.).
This Galvanic Corrosion Table says that the "anodic" or "less noble" metals at
the negative end of the series such as
magnesium, zinc and aluminum - are more likely to be attacked than those at the
"cathodic" or "noble" end of the series such as gold and graphite.
The critical point is the difference in potential of the two materials being
considered as a joined pair.
A difference of hundreds of millivolts is likely to
result in galvanic corrosion, but only a few tens of millivolts is unlikely to
be a problem.
Galvanic corrosion is a localized mechanism by which metals can
be preferentially corroded.
This form of corrosion has the potential to attack junctions of metals, or regions where one construction metal is changed to another.
Frequently this condition arises because different metals are more easily fabricated into certain forms; an example might be a door frame manufactured from aluminum extrusions (aluminum extrudes extremely well into architectural sections), but with a door handle fabricated from stainless steel tube to exploit its higher strength and abrasion resistance.
We suggest you to have a look also at these pages:
Seawater Corrosion Rates of Metals
Galvanic Series of Metal in Seawater
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