In which environment is galvanic corrosion usually more severe?

Galvanic corrosion is typically more severe in saltwater environments compared to other options. This is due to the increased conductivity of saltwater, which enhances the electrical conductivity necessary for galvanic cells to form between dissimilar metals. In a saltwater environment, the presence of dissolved ions facilitates the electrochemical reactions responsible for galvanic corrosion, accelerating the corrosion process significantly.

In freshwater, while galvanic corrosion can occur, the lower conductivity due to the absence of salts leads to reduced corrosion rates. Air can also contribute to corrosion through oxidation, but it does not create the same electrochemical conditions as a conductive liquid, making galvanic corrosion less severe in that setting. Ground conditions can lead to corrosion as well, influenced by moisture and soil chemistry, but again, the conductivity levels and mechanisms involved are typically not as aggressive as in saltwater scenarios. Hence, the unique properties of saltwater make it a more conducive environment for galvanic corrosion to occur and escalate rapidly.