What type of corrosion is primarily addressed by cathodic protection?

Cathodic protection specifically targets galvanic corrosion by preventing the loss of metal from a structure through electrochemical means. In the process of galvanic corrosion, two dissimilar metals in the presence of an electrolyte create a galvanic cell, where the more active metal (anode) corrodes at an accelerated rate while the less active metal (cathode) is protected. Cathodic protection achieves its objective by supplying electrons to the metal surface, effectively making it the cathode in electrochemical reactions, which reduces its propensity to lose metal ions.

This method is particularly effective for marine environments where structures such as hulls, tanks, and pipelines come into contact with seawater, enabling corrosion to occur. By using sacrificial anodes—anodes made of a more reactive metal than the protected structure—or impressed current systems, the cathodic protection method redirects the corrosion process, thus preserving the integrity of the metal from galvanic corrosion.

Localized corrosion, uniform corrosion, and stress corrosion cracking are forms of corrosion that involve different mechanisms and do not directly utilize cathodic protection as their primary mitigation technique. Localized corrosion can occur under protective coatings, uniform corrosion affects surfaces uniformly over time, and stress corrosion cracking involves the combination of tensile stress and a