Eco-friendly metal coating replacement for chromate

摘要

CSIRO has developed a novel coating technology, "Quench Coat", to protect galvanised products from 'white rust' - the form of zinc oxide that tarnishes freshly galvanised coatings, making them look dull. Currently Australian galvanisers use a chromium-based treatment immediately after galvanising, to maintain a shiny appearance during the early life of the product. Chromate is widely used as a conversion coating on metals such as zinc, aluminium and magnesium to help protect against short-term corrosion and as a base for additional protective coatings. However, although chromate is an excellent corrosion inhibitor, it is highly toxic.