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Metal Finishing Services

What is Iridite NCP?

Iridite NCP is a chrome-free passivation process suitable for components made of Aluminium Alloys. It provides an excellent level of corrosion resistance and acts as a base coat for Paint and Powder applications. Iridite NCP meets ELV, RoHS and WEE directives and is a suitable replacement for Alodine/Alocrom. 

What is the Process?

As a passivation process, the application of Iridite NCP is a non-electrolytic in nature and typically involves immersion of components into an acidic solution. This process is often referred to as being a conversion coating where by a coating is formed through a chemical reaction with the base metal. In order to obtain the best possible results, components will often have to undergo a number of cleaning processes to remove surface impurities which are all carried out in house. 

What are the Advantages?

Iridite NCP is free of Cadium, Lead, Mercury, Chromium and PBB/PBDE compounds meaning it will meet environmental standards such as ELV, RoHs and WEEE.

Iridite NCP is often used as an undercoat for other processes, it can provide excellent adhesion for paints, sealants and adhesives as well as paint and powder coating. Most non-chrome conversion coatings are based on polymer and fluoride compounds, and where these have excellent adhesion characteristics, in most cases they don’t offer corrosion resistance which Iridite NCP is able to do.Iridite NCP is able to provide most aluminium alloys with over 1000 hours of protection in salt spray tests, and this can be increased when combined with other processes. Iridite NCP is able to operate at high temperatures up to 350 degrees Celsius and unlike chromate conversions requires no oven curing time.

Iridite NCP offers a good level of electrical conductivity which is comparable to conventional chromate coatings and is often used on applications involving Electrical grounding. 

Specifications Offered:

MIL spec 5541, MIL-C5541 Class III

What We Offer

Silchrome Plating can provide Iridite NCP coating for components up to 650 x 500 x 605mm.
All our processes are carried in house at our production facility in Leeds and Silchrome Plating are IS0 9001 AND ISO 14001 approved. 

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  • The official logos for the ISOQAR and UKAS industry regulatory bodies.