What type of corrosion occurs between two different metals?

Galvanic corrosion occurs specifically when two different metals are in electrical contact with each other in a corrosive electrolyte, leading to the accelerated corrosion of the more anodic metal. When dissimilar metals are coupled, one acts as the anode and the other as the cathode, with the anode experiencing oxidation, or the loss of metal due to corrosion. This electrochemical reaction is driven by the different potentials of the metals involved, which creates a galvanic cell.

The presence of an electrolyte is crucial because it facilitates the flow of ions, sustaining the corrosion process. This makes galvanic corrosion particularly significant in marine environments where saltwater acts as an efficient electrolyte. Understanding this type of corrosion is vital for marine applications, where the use of different metals is common, and can lead to significant material degradation if not managed through proper design and protective measures, like coatings or the use of sacrificial anodes.

Other types of corrosion mentioned, such as uniform corrosion, electrochemical corrosion, and stress corrosion cracking, involve different mechanisms or conditions. Uniform corrosion affects a material uniformly across its surface, electrochemical corrosion refers to the chemical reactions that involve electron transfer (which can encompass galvanic processes), and stress corrosion cracking involves the interaction between tensile stress and a