Preparation And Characterisation Of Cerium Doped Silica Sol-Gel Coatings On Glass And Aluminium Substrates

Chromates are among the most common substances used as corrosion inhibitors. However, these compounds are highly toxic, and an intense effort is being undertaken to replace them. Cerium compounds seem to fulfill the basic requirements for consideration as alternative corrosion inhibitors. The aim of this work was to study the effect of the incorporation of cerium ions in silica sol-gel coatings on aluminium alloys as potential replacement of chromate treatments. The main idea was to combine the "barrier" effect of silica coatings with the "corrosion inhibitor" effect of the cerium inside the coatings. Thin and transparent cerium doped silica sol-gel coatings were prepared by dipping 3005 aluminium alloys in sol-gel solutions.