What is galvanic corrosion?

Galvanic corrosion occurs specifically when two dissimilar metals come into contact in the presence of an electrolyte, such as moisture. This type of corrosion is driven by a fundamental electrochemical reaction, where one metal acts as an anode (which corrodes) and the other as a cathode (which remains protected). The metal that is less noble or more reactive will corrode preferentially. For example, if you have a copper wire and an aluminum fixture connected with moisture present, the aluminum may corrode due to its higher reactivity compared to copper.

This phenomenon highlights the importance of understanding material compatibility in electrical systems and the potential need for protective measures, such as coatings or the use of similar materials, to mitigate galvanic corrosion risks.