Effect of Nano Cerium Oxide on Cathodic Protection and Barrier Properties of Zinc Rich Bitumen Coatings

摘要

The application of the zinc-rich coating on steel structures is an effective way of protecting against corrosion. The aim of this research is to assess the effect of cerium oxide nanoparticles on the corrosion resistance and cathodic protection properties of zinc-rich bitumen coatings on steel St37. The coating behaviors were examined using electrochemical impedance spectroscopy, open-circuit potential measurements, adhesion, salt spray corrosion, and immersion tests. FTIR analysis was used to study the interaction between nanoparticles and bitumen. Different amounts of nano cerium dioxide particles were dispersed into the zinc rich bitumen matrix by the ultrasonication. EIS and open circuit potential survey indicated that in the presence of cerium oxide nanoparticles, the corrosion resistance and sacrificial properties of zinc rich coatings enhanced. In addition, salt spray and immersion test confirmed the improved corrosion protection of zinc rich bitumen with nanoparticle and illustrated that coatings with 3% CeO2 had optimum corrosion behavior by reducing the penetration paths of water and corrosive ions to steel substrate. Cross cut and pull off test indicated that after corrosion test, coatings were more adhesive in the presence of cerium oxide due to the barrier properties of nanoparticles.