Sacrificial protection is a process that prevents corrosion by utilizing the properties of a zinc coating.

Even if the zinc layer is scratched and iron is exposed, the zinc around the damaged area will preferentially dissolve because its ionization tendency is greater than that of iron. This provides electrochemical protection to the iron surface, preventing it from rusting.

While a paint or resin coating offers good corrosion resistance initially, a defect or scratch in the film will cause the exposed iron to rust and corrode. A zinc coating, however, is able to prevent this from happening under the right conditions.