What are the two most common materials used for sacrificial anodes?

Sacrificial anodes are crucial components used to protect metal structures, such as pipelines and ships, from corrosion. The most common materials used for sacrificial anodes are zinc and magnesium due to their electrochemical properties and their effectiveness in various environments.

Zinc is often used in marine applications because it has a high driving voltage, which makes it a very effective anode. It provides cathodic protection by corroding in place of the steel or other metals it is protecting, thus prolonging the life of these structures.

Magnesium is also an excellent choice for sacrificial anodes, particularly in soil and freshwater environments, where its potential is optimal for protecting ferrous metals against corrosion. The use of magnesium is effective in a variety of industrial applications, including underground pipelines and tanks. Its electrochemical activity allows it to effectively shield other metals from corrosion.

Together, zinc and magnesium are widely recognized and utilized for their ability to significantly reduce corrosion rates in metals, making them the best choice for sacrificial anodes in many applications.