Anticorrosive Performance of Epoxy/Clay Nanocomposites Pre-Treated by Hexafluorozirconic Acid-Based Conversion Coating on St12

In this research, epoxy composites were prepared using 3 wt%loadings of clay nanoparticles Corrosion resistance behavior of epoxy coating containing various clay percentages was investigated on steel by electrochemical impedance spectroscopy (EIS). Moreover, the modification of substrate was accomplished using conversion coating based on hexafluorozirconic acid. The electrochemical results revealed that the pre-treated coating with 3 wt% nanoclays possesses the best anticorrosive performance (2.5×108 Ω.cm2) after 2 weeks immersion in 3.5 wt% NaCl solution. In addition, pull-off technique was employed to measure the adhesion strength of coatings to metallic substrate. Experimental results exhibited that conversion coating impressively increased the corrosion resistance and coating adhesion as well.