Ferrophosphorus is an alloy of iron and phosphorus. It contains high proportion of iron phosphides, Fe2P and Fe3P. The usual grades contain either 18 or 25% of phosphorus. It is a gray solid material with melting point between 1050-1100 °C. It may liberate phosphine in contact with water. Very fine powder can be combustible.
1. Used in metallurgy as a source of phosphorus for alloying, for deoxidizing the melt and for removal of unwanted compounds into slag.
2. Addition of ferrophosphorus is used to produce powder metallurgy (P/M) steels with favorable magnetic properties, e.g. high saturation induction. Iron phosphide acts here as a solid solution hardener and a sintering aid.
3. Can be added to cast iron, where the phosphorus improves fluidity and therefore quality of the castings, can increase wear resistance and cutability. In steels its addition to some alloys can improve corrosion resistance.
4. Used as a construction aggregate for production of high-density concrete for radiation shielding, as an alternative to usually used steel punchings and shot. It can be used with both Portland cement and magnesia cement.
5.Reacted with sulfur or pyrite, is used for production of phosphorus pentasulfide.
6. Used for production of lithium iron phosphate, necessary as electrode material for LiFePO4 batteries.
7. Used instead of zinc powder in some paints and coatings. It has good adhesion, anticorrosive properties, electrical and thermal conductivity, and wear resistance.
8. Used as a reducing agent to produce sodium or potassium from sodium carbonate or potassium carbonate.