Coatings based on alkoxides precursors for corrosion protection in galvanized steel

摘要

The chromate coatings base are widely recognized for their effectiveness as pre-treatment for corrosion protection. However, it is known that ions of Cr~(+6) present in the chromate solution are regarded as highly toxic and carcinogenic. Therefore, coatings potential substitutes have been studied worldwide. Among the alternatives to treatments based on Cr~(+6), silanes demonstrate some important advantages such as low environmental impact and compatibility with a wide range of inorganic and organic interfaces. In this work was conducted on the application in a galvanized steel of the hybrid film obtained from a sol composed by the system the combination of alkoxides precursors 3- (trimethoxysilylpropyl) methacrylate (TMSM) and tetraethoxysilane (TEOS), with addition of a corrosion inhibitor based on Ce~(3+). The films obtained by dip-coating process, were characterized by electrochemical and morphological behavior. It was observed that the addition of inhibitor is positive and improves the performance of the alkoxides precursors coating.