Novel corrosion protective coatings for aluminium alloys and steels based on oxidic nanoparticles

Abstract

Abstract Based on chemical nanotechnology glass-like protective coatings thermally processed at comparatively low temperatures of around 500 °C were developed for aluminium and steel substrates by two different means. Starting from polymeric sols containing a multicomponent oxide of the SiO2 – B2O3 – P2O5 – Na2O system produced by sol-gel technology under acidic conditions, coatings were developed which are thin, hard, transparent, crack-free and corrosion resistant. Electrophoretic deposition of coatings from particulate sols containing multicomponent oxide synthesised under basic conditions proved to be a promising method when very thick coatings are required. Both routes offer the potential of a new type of purely inorganic coatings for corrosion and abrasion protection.