It can be used in steel and metal manufacturing processes. The compound is chemically bonded to the metal surface and prevents further oxidation of the metal. Its presence is partially responsible for the corrosion resistance of the Iron pillar of Delhi.
Iron Phosphate coatings are also primarily used as base coatings for paint in order to increase adhesion to the iron or steel substrate, and is often used in rustproofing as well. It can also be used for bonding fabrics, wood, and other materials to these surfaces as well. Iron Phosphate coatings are usually applied as part of a painting or powder coating process.