What type of corrosion is caused by the use of dissimilar metals?

Galvanic corrosion occurs when two dissimilar metals are electrically connected in a corrosive environment, leading to an electrochemical reaction. In this process, the more anodic metal (the one that is more susceptible to corrosion) begins to corrode faster, while the more cathodic metal (the one that is more resistant to corrosion) is protected. This phenomenon arises because differences in the electrochemical potential of the two metals create a galvanic cell, which accelerates the corrosion of the anodic metal.

Understanding this type of corrosion is crucial in water treatment and distribution systems, where different metals might interact. For example, if copper pipes are connected to iron fixtures, the copper could corrode at an increased rate due to its position in the galvanic series compared to iron. Proper materials selection and protective measures, such as insulation between dissimilar metals, can help mitigate galvanic corrosion in water systems.