Coating of Steel by Long Alkyd Resin Reinforced with SiC Nanoparticles to Improve its Corrosion Resistance

To improve the properties of the organic coatings ceramic nanoparticles can be applied. In the present study, inorganic-organic nanocomposite coating contains SiC nnoparticles and alkyd resin was applied on the stainless still substrates. In this regard 1, 2 and 3 wt% of SiC nanoparticles were used to prepare the nanocomposite. In order to achieve a homogeneous mixture of nanoparticles and polymeric resin, magnetic stirrer and ultrasonic device were used. The coatings were deposited on the substrates by dipping technique. To study the morphology thickness and surface of the coatings, scanning electron microscopy (SEM) and atomic force microscopy (AFM) were used. The corrosion resistance of the coatings was investigated by polarization Tafel test, electrochemical impedance spectroscopy (EIS) and salt spray. Corrosion test results showed a reduction of corrosion current and an increasing in the corrosion resistance of substrate with nanocomposites coating and the sample with 3 wt% nanoparticles was selected as optimum sample by reducing current density from 9/2×10-6 to 2/2×10-9. The results of adhesion test by cross-cut method showed the reduction of coating separation from 9% to 4%. The coating thickness of sample was measured about 20 μm.