European Union Directives ban Cr6+ use in electrical products from July 2006 and also in cars and light vans from July 2007. The two EU Directives will come into effect banning hexavalent chromium (amongst other toxic substances) from fasteners used in certain markets.
The Waste Electrical and Electronic Equipment (WEEE) and Restriction of Hazardous Substances regulations (RoHS) ban Cr6+ Hexavalent from new battery or mains powered products sold from July 2006.
The End of Life Vehicle Directive (ELV) bans Cr6+ Hexavalent Chromium from new cars and light vans sold from 1st July 2007 regardless of date of manufacture.
Hexavalent Chromium (Cr6+, Cr(VI) or Chrome 6) is a highly toxic form of Chromium, which may, if dumped in landfill sites, contaminate water supplies. Cr6+ is a soluble form of chromium used in producing chromate films applied to electrolytic zinc plated coatings to increase their anti corrosion capabilities.
Cr6+ is a Category 1 carcinogen, toxic by inhalation, skin contact or ingestion. It can cause long term adverse effects in the aquatic environment, hence concerns about its presence in landfill resulting in contamination of water systems.
Vehicle and Electrical Manufacturers are already demanding alternatives to meet these requirements.
Currently there is no existing or known proposed legislation banning Cr6+ use on fasteners for markets outside the European Union.
Alternative coatings have been developed using Trivalent Chromium (Cr3), which does not have the same toxic characteristics.
Cr6+ free coatings have been available for some time. Recent research has developed systems for the automotive sector that, as well as eliminating Cr6+, provide high levels of corrosion resistance.
Many of these new systems use Trivalent passivates (Cr3), which do not contain hexavalent chromium compounds.
Two types are now produced. Thin film systems provide a decorative and basic corrosion protection coating. Thick film systems provide much higher corrosion protection to meet automotive specifications.
All thick film trivalent passivates deliver better protection than the Cr6+ systems they replace. They also provide superior resistance to thermal shock. They do not, however, possess the self-healing capabilities of their Cr6+ predecessors.
Supplying non-compliant fasteners to the automotive or electronic sectors could lead to expensive liability and recall claims.