Evaluation of new core-shell pigments on the anticorrosive performance of coated reinforced concrete steel

Pigments are considered as the major content of paints that can help in preventing corrosion. In this work, epoxy based pait system was applied on reinforced concrete steel to evaluate its anticorrosive performance. This system is based on new core-shell pigments which are composed of a core of different calcium carbonate sources (natural calcite, marble waste and eggshell) covered with thin shell of zinc ferrite to compare their anticorrosive effect. The corrosion resistance of the coatings was evaluated in 3.5 % NaCl for 28 days via two electrochemical methods; open circuit potential (OCP) and electrochemical impedance spectroscopy (EIS). The measurements revealed that coated concrete steel with paints containing zinc ferrite/marble was the best in its corrosion protection performance showing that although the cores are all based on calcium carbonate, the source can affect the performance.