Duplex coating – corrosion protection

Duplex coating – corrosion protection

Written by Kobout I READING TIME 6 MINUTES
A Duplex coating is the perfect treatment for parts which have to meet the strict requirements as formulated in the ETAG 006 standard. This type of coating is made of an electrolytic base layer in combination with an organic top coating. This guarantees an extremely high corrosion protection with chemical resistance. Thanks to the chemical resistance and high corrosion protection this surface treatment is very suitable for different applications such as offshore, industry, construction and construction of stables.

Electrolytic zinc layers are usually passivated or chromated (called chromating when using Cr 6+). By using the unique properties of a passivated zinc layer (free of Cr 6+) with an organic top coating, outstanding corrosion resistances are obtained. Duplex is available in several colours: red, green, yellow, brown, dark brown, blue, black and silver grey. The corrosion resistances apply to the silver grey top coating. If you are looking for a good corrosion resistance, as well as chemical resistance, Duplex will be highly suitable, 15 Kesternich resistance cycles (with 2, OLS SO2) are no exception. Duplex provides the highest possible resistance where extreme environmental factors have influence. The use of stainless steel in swimming pools may result in corrosion as a result of the high content of choloride and ozone. Duplex is a superior alternative. Besides, Duplex is ideal for parts applied in coastal areas with salt-containing, humid air, industry and construction of stables where the strong ammoniac emission is an issue. You see, the top coating is well resistant to aggressive acids, alkalis and gases. In order to distinguish the several Duplex series, the names are given including the corrosion resistance. For example: Duplex 1000, with 1,000 hours salt spray test according to DIN 50 021 NSS.


  • Retards contact erosion.
  • Protects against chemicals such as acids, alkalis, oils, gasoline etc.
  • Available in 8 colours; standard is silver grey.
  • Can be provided with an extra friction retarder (GZ).
  • Treatment temperature < 220°C => no deformation, no loss of hardness
  • Meets ELV (2000/53/EG): free of chrome, cadmium, nickel, lead, mercury and molybdene.
  • Meets RoHS (2002/95/EG).

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