Aplicación de la técnica de ruido electroquímico al estudio de pinturas anticorrosivas

R. ROMAGNOLI; M. DEYÁ; G. BLUSTEIN; B. DEL AMO

Recife, Brasil

Congreso; 28º Congresso Brasileiro de Corrosao, 2nd International Corrosion Meeting; 2008

The objective of this paper was to explore the capablities of the electrochemical noise technique to study the corrosion process in painted metals. It would be desirable that the technique may differentiate among different paint systems. In this sense, four different paint systems were studied. Three anticorrosive paints formulated with an alkyd resin wer tested. Two of them contained zinc phosphate as anticorrosive pigment but with two different contents: 10 and 30% by volume with respect to the total pigment content; the other contained 10% of zinc phosphate plus a zeolite modified with molybdenum compounds. The other coating was a chromate based primer, applied on galvanized steel. Noise spectra were obtained at 1 Hz and the statistical analysis of date were performed. Results show that the electrochemical noise technique can differentiate among the different paint systems and allow to detect the different processes on the metallic substrate which are responsible for coating degradation.