Galvanic corrosion is an electrochemical process in which one metal corrodes preferentially when it is in electrical contact with another, in the presence of an electrolyte. A similar galvanic reaction is exploited in primary cells to generate a useful electrical voltage to power portable devices. This phenomenon is named after Italian physician Luigi Galvani (1737–1798).
Corrosion of an iron nail wrapped in bright copper wire, showing cathodic protection of copper; a ferroxyl indicator solution shows colored chemical indications of two types of ions diffusing through a moist agar medium
Regular maintenance checks discovered that the Statue of Liberty suffered from galvanic corrosion
Aluminium anodes mounted on a steel-jacketed structure
Electrical panel for a cathodic protection system
Corrosion is a natural process that converts a refined metal into a more chemically stable oxide. It is the gradual deterioration of materials by chemical or electrochemical reaction with their environment. Corrosion engineering is the field dedicated to controlling and preventing corrosion.
Corrosion on exposed metal, including a bolt and nut
Galvanic corrosion of an aluminium plate occurred when the plate was connected to a mild steel structural support.
Gold nuggets do not naturally corrode, even on a geological time scale.
Normal microstructure of Type 304 stainless steel surface