Zinc-rich primers are a type of protective coating that provides exceptional corrosion resistance to steel surfaces. They contain a high concentration of metallic zinc powder suspended in a resin binder, typically epoxy or inorganic zinc silicate. How Zinc-rich Primers Work: The key to their effectiveness lies in the principle of sacrificial protection. When applied to steel, the zinc particles create a galvanic barrier. Zinc is more reactive than steel, so it preferentially corrodes (oxidizes) instead of the underlying steel. This sacrificial corrosion process forms a protective zinc oxide layer that shields the steel from further corrosion.