The use of hexavalent chromium is also of particular concern in standard anodizing applications. As a result of existing alternatives being available for many years, anodizing is not specifically mentioned in the REACH legislation under Annex XIV and in ECHA.
Existing alternatives include SAA, Sulfuric Acid Anodizing, and BSAA, Boric Sulfuric Acid Anodizing. SAA is for general applications and effective through the use of a trivalent seal top coat. BSAA is the aerospace alternative developed by Boeing to resolve concerns over a loss of fatigue strength resulting from the use of non-chromic acid anodizing systems. Both perceived and real inefficiencies have been and still is the main reason that Cadmium as a plating media is still used in some defense and aerospace applications, particularly for landing gear on aircraft. Sealers as undercoats for paint utilizing SAA and either trivalent chrome or nickel based seals are also non CrVI alternatives available in the marketplace.
As a result of these numerous and viable alternatives, it’s very difficult to find chromic acid anodizing in practice for many applications in present day. With one exception being limited to department of defense applications that still process CrVI, although these applications are also gradually transitioning to the SAA or BSAA alternatives.
In summary, a full range of alternatives to chromic acid anodizing, sealers and paint undercoats are already widely available.
For more information, please visit the links provided below.
Aluminum Anodizers Council (AAC)
The Aluminum Anodizers Council is a progressive and influential industry force, serving members through education, advocacy, and promotion of anodizing worldwide.
The Aluminum Association works globally to aggressively promote aluminum as the most sustainable and recyclable automotive, packaging and construction material in today’s market.
Chemical Coaters Association International (CCAI)
Chemical Coaters Association International is a technical and professional organization that provides information and training on surface coating technologies.
This ‘homepage for the finishing industry’ is a broad resource for the anodizing, plating, powder coating and surface finishing arts.
National Association for Surface Finishing
NASF is a membership trade association whose mission is to promote the advancement of the North American surface finishing industry, with nearly 3,000 professional and student members.
National Paint & Coating Association
NPCA is a century-old voluntary, nonprofit trade association representing paint and coatings manufacturers in dealings with the US government.
Precision Metalforming Association (PMA)
PMA is the full-service trade association representing the metal forming industry of North America, which creates precision metal products using stamping, fabricating, spinning, slide forming and roll forming technologies, and other value-added processes.