Calcium monofluorophosphate: a new class of corrosion inhibitors in NaCl medium

The effect of a new class of corrosion inhibitors, namely the monofluorophosphate of calcium, on the corrosion of iron, nickel, and copper in 3% NaCl solution has been investigated using potentiodynamic polarisation, measurement of open circuit potential, X-ray photoemission spectroscopy (XPS), and scanning electron microscope (SEM) techniques. The addition of an increasing concentration of calcium monofluorophosphate causes a shift of the corrosion potential in the positive direction, with a decrease of the anodic current density. The adsorption characteristics of this compound on the metal surface play a significant role in the inhibition process.