Chloride corrosion resistance of double-layer anticorrosive coating in simulated concrete pore solution

Abstract

Abstract Steel reinforced concrete structures are widely used in construction projects due to their low cost and high load-bearing capacity. The service life is inevitably reduced because of the steel corrosion during service. Here, a double-layer anti-corrosion strategy was proposed for the low carbon steel used in chloride corrosion environment. A super-hydrophobic anti-corrosion coating was fabricated on the surface of low carbon steel bars by an environment-friendly and safe method. The corrosion resistance of super-hydrophobic low carbon steel was studied in a chlorine-containing simulated concrete pore solution. Electrochemical test results showed that super-hydrophobic low carbon steel had better chlorine corrosion resistance than ordinary low carbon steel. Moreover, the effects of three different modification methods on the chloride corrosion resistance of super-hydrophobic low carbon steel were compared. The results of electrochemical tests and corrosion immersion experiments showed that the super-hydrophobic surface obtained through a combination of physical and chemical modification had good corrosion resistance. The corrosion inhibition rate of the super-hydrophobic samples was up to 97.1%. It is expected that the super-hydrophobic low carbon steel with a dual anti-corrosion layer will play a significant role in the corrosion protection of steel reinforced concrete structures.