galvanic series
The galvanic series is a ranked list of metals and alloys according to their electrochemical reactivity with each other while in a given environment, usually seawater or some kind of electrolyte. The importance of this ranking is for predicting galvanic corrosion that will occur when two dissimilar metals, in electrical contact with each other, find themselves in the presence of an electrolyte.
Key Features:
- Electrochemical Ranking: Most anodic metals (active, more easily corroded) are listed first in baptism; the least anodic metals are ranked after them. More anodic metals corrode more quickly in contact with cathodic metals than vice versa, helping to select metals for unwanted corrosion on metal structures.
- Corrosion Prediction: Used to tell which metal is going to corrode preferentially in a galvanic couple. The greater the spacing of two metals along the series, the riskier the galvanic corrosion. Engineers can use this series in making material compatibility selection for marine, construction, and industrial applications.
- Common Applications: Marine engineering, including shipbuilding and offshore platforms, to avoid corrosion in saltwater. Avoid corrosion in battery terminals and connectors in the electronics and automotive industry. Corrosion design of pipeline and structural applications for metal combinations that resist corrosion.
Understanding the galvanic series is a key to prevention of corrosion and selection of materials. Engineers refer to this series while designing structures and components for durability in aggressive environments.