Manganese phosphating (or phosphating) is a dark gray coating of phosphate material with anti-rust and anti-seize properties. The color tone and the thickness of the phosphating depend both on the type of material and the parameters of the bathroom. Manganese phosphating has the advantage, compared to other surface treatments, to guarantee a constant thickness coating over the entire surface.

The phosphating allows a long corrosion protection of the parts subject to sliding.


The main applications of manganese phosphating are:

  • Anticorrosive iron function:
    The laboratory tests confirm that, after appropriate oiling, the particular manganese phosphatate exceeds 50-100 hours of resistance in salt spray. Thanks to its porosity the phosphate coating is able to absorb large quantities of oil and keep it in contact with the surface.
  • Anti-wear function: 
    Unlike zinc phosphating, manganese phosphating is able to reduce the friction between surfaces in reciprocal sliding, acting on both the parameters that limit friction: lubrication and reduction of roughness. After a very short running, in fact, the crystals on the sliding surfaces they smooth the peaks and make them perfectly specular to each other. At the same time, the cavities still present in the phosphate carryover act as lubricant reserves.

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