Anticorrosive performance of duplex systems on steel surfaces

Galvanized steel specimens were coated with four different organic systems, containing either special acrylic resins or epoxy resins with or without wash primer. The anticorrosive performance of these duplex systems when exposed to an environment of 3.5 percent w/w NaCl solution, was investigated by electrochemical impedance spectroscopy, corrosion potential monitoring, potentiodynamic polarization and dielectric measurements. Interrelation of the obtained results, confirmed by visual observations after salt spray and weathering tests, shows that all four coating systems are more protective than simple galvanizing. The system, comprising a wash primer, a two‐component epoxy resin primer and an epoxy resin finish paint, demonstrates the best anticorrosive behavior among the four systems examined.