Chromate Conversion Coatings

Chromate conversion offers a cost effective non-electrolytic process for coating aluminium resulting in excellent corrosion resistance, a good pre-paint finish and good adhesion qualities. The surface thickness of an Alocrom coating is about 2µm thick. We offer 3 chromate conversion processes, Alocrom 100, 1000 & 1200 as detailed below.

Alocrom 100

Alocrom 100 offers excellent corrosion resistance and is typically used in the food and water processing industries because it contains no hexavalent chromium. Alocrom 100 typically produces an iridescent blue/green finish.

Alocrom 1000

Alocrom 1000 produces a clear chemical film on the surface of the aluminium and offers excellent electrical conductivity. Whilst the Alocrom 1000 process utilises hexavalent chromium none of this is detectable in the final dry surface finish if the process is carried out in accordance with manufacturer’s guidelines. We offer a suitable alternative for customers that require a wholly non-chromate conversion.

Alocrom 1200

Alocrom 1200 produces a gold coloured coating which offers good electrical conductivity and corrosion resistance and is the most common Alocrom finish requested by our customers. Whilst the Alocrom 1200 process utilises hexavalent chromium none of this is detectable in the final dry surface finish if the process is carried out in accordance with manufacturer’s guidelines. We offer a suitable alternative for customers that require a wholly non-chromate conversion.

Service Outline

The table below details the relative properties of Alocrom 100, 1000, & 1200:

Property	Alocrom 100	Alocrom 1000	Alocrom 1200
Colour	Iridescent Green	Clear	Gold
Conductivity
Corrosion
Length	910mm (3')	1820mm (6')	1820mm (6')
Width	457mm (1.5')	457mm (1.5')	457mm (1.5')
Depth	910mm (3')	910mm (3')	910mm (3')
Standards	--	DEFSTAN 03-18 Clear MIL-C-5541 Class 3	DEFSTAN 03-18 MIL-C-5541 Class 1