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Does Rust Conduct Electricity?

I was wondering if rust is metal does rust conduct electricity?

Or is it a barrier?


Thanks in advance.

Christian Rivas
IT - Houston, Texas
2007

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Rust is iron oxide and does not conduct electricity. But it is a very poor barrier because it is non-adherent and attracts moisture.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2007

Conductivity is relative, so what is your criteria. Some rust will hold enough moisture that it is somewhat conductive.

James Watts
- Navarre, Florida
2007

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Rust is a mixture of iron oxides, including Fe2O3, FeO(OH) and FeO. In its pure state it will not conduct electricity, but if impure and if it has some free iron still in its matrix it may conduct electricity, depending on how much free iron is present. As the others have said, it also contains and retains water, so electricity can pass through the water and appear to make the rust conducting. As with many things in science, the answer is not always that easy - the theory and the facts can differ. In this case the simple answer is no, but the practical answer is that under some circumstances rust can appear to be conducting.

Trevor Crichton
R&D practical scientist
Chesham, Bucks, UK
2007