What material is typically used to make sacrificial anodes?

Sacrificial anodes are typically made from materials that are more reactive than the metal they are protecting, which allows them to corrode preferentially. Magnesium is commonly used because of its high electrochemical potential, which makes it an excellent choice for protecting metal structures from corrosion, especially in environments like water tanks and pipelines.

By using magnesium as a sacrificial anode, it effectively "sacrifices" itself; as it oxidizes, it creates a protective galvanic action that helps to prevent corrosion on the surface of the metal it is attached to. This characteristic makes magnesium an ideal material for sacrificial anodes in various applications, particularly in water treatment systems where corrosion control is paramount.

Other materials like aluminum and zinc can also be used for sacrificial anodes in some contexts, but magnesium is often favored for its efficiency and effectiveness in specific applications, especially in fresh water environments. Copper and iron do not serve as suitable materials for sacrificial anodes due to their lower reactivity compared to other options available.