Electrochemical Noise Analysis for Evaluating the Protection Properties of Al_2O_3 Nanoparticles Epoxy Coating for Steel Bar

Objective To study the protective performance of Al2O3nanoparticles epoxy composite coating of steel. Methods The Al2O3nanoparticles were prepared,and then added into the epoxy coating,coated on the steel as a film. The Al2O3nanoparticles were characterized by XRD and SEM. The anti-corrosive properties of the composite coatings in the solution of 3. 5% NaCl were evaluated by electrochemical noise and electrochemical impedance spectroscopy. Results The average size of Al2O3nanoparticles was 75 nm. Based on the time and frequency domains analysis of electrochemical noise data,the analysis of electrochemical impedance spectroscopy and data fitting,it was found that the composite coating with 0. 1% Al2O3nanoparticles( as a percentage in the weight of epoxy resin) had the best protective performance on steel. Conclusion The epoxy coating supplemented with a suitable amount of Al2O3nanoparticles showed significantly improved protective performance on steel.