What Does Corrosion Cell Mean?
Corrosion cells are a condition on a metal surface in which a flow of electric current occurs between the metal surface and an electrolyte with which it is in contact sufficient to cause the metal to degrade. Corrosion cells have been designed to measure the corrosion properties of an object immersed in an electrolyte. It is normally used to test the reaction of metal specimens in a corrosive environment.
Corrosion cells can be created through:
- Electrolysis
- Oxygen concentration cells
- Galvanic action
Corrosionpedia Explains Corrosion Cell
A corrosion cell is a condition on a metal surface where flow of electric current occurs between two metal surfaces.
A corrosion cell consists of four fundamental components:
- Anode
- Cathode
- Conducting environment for ionic movement (electrolyte)
- Electrical connection between the anode and cathode for the flow of electron current
The driving force behind a corrosion cell is a potential or voltage difference between the anode and cathode. It is important to know that each of the four elements of the corrosion cell affect the severity of corrosion.
A corrosion cell can occur on the molecular level. These cells usually are produced by three factors:
- Irregularities in the metal's surface produced by the original metalworking/forming or extruding
- Differences in the composition of the metal's surface pressed into the surface by shaping/rolling or finishing operations
- Stresses induced from forming, welding, etc.
Coating films can be used to control one of these elements - the electrolyte. Applying a tightly adhered continuous protective film over the surface of the metal and isolating those points with different potential (anode and cathode) controls corrosion.