Process Phosphating
Three methods.
Iron phosphating, used to provide steel surfaces with good adhesion to paints.
Zinc phosphating, used against corrosion and as pre-treatment for steel and aluminium surfaces, prior to painting or oiling for cold flow pressing.

Finally, mangano phosphating which impede the adhesive wear of mechanical parts of internal combustion engines, or bearings.
Typical thickness lies between 3 and 50 micron.

The process forms a layer of insoluble phosphates on a metal surface using an agent containing phosphoric acid and/or phosphates. The pH value, rising on the surface, allows the formation and precipitation of the phosphates on it (and not in the bath).
Danish Name Fosfatering
Category Surface treatments, Electroless plating
Materials Substrates:
Zinc (steel electroplated parts)
Steel
Typical products Cog-wheel (Zn)
Mining-timber (Zn)
Nut (Mn)
Spring, phosphating (Mn)
Competing processes Chromating
References Alumatic A/S
BM Lakering A/S
Nycoat ApS
Rudolf Clauss GmbH
Price notes Indicative price: 3,8 DKK/kg of substrate.
If compared to the price of the final product, the cost of phosphating is, at most, one percent of it, and therefore almost negligible.
Price date March 1997
Photo Thomas Nissen (Computer graphics)
Copyright © 1996-2003 Torben Lenau
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