Vol. 42, Iss. 2

The actual working environment of ship ballast water tanks is extremely harsh, making corrosion protection of ballast tanks critical for ensuring ship safety. This study systematically evaluated the microbial corrosion resistance of corrosion-resistant coatings in ship ballast water tanks, with a focus on analyzing the corrosion mechanisms and protective strategies of sulfate-reducing bacteria (SRB) on coatings. Through comparative experiments, the corrosion mechanisms of SRB were revealed. Electrochemical testing was employed to investigate the efficacy of the corrosion-resistant coatings. The i\({}_{corr}\) values of electrodes 1–5 in the coating group ranged from 0.038 to 0.193 \(\mu\)A·cm\(^{-2}\), while the i\({}_{corr}\) value of electrode 6 was significantly lower than that of the Sterile 6 electrode, at 0.038 \(\mu\)A·cm\(^{-2}\). When the addition of GO and rGO was both 200 ppm, the uniform corrosion rate of carbon steel was the lowest, at 0.078 mm/a and 0.097 mm/a, respectively.

Polymer materials are widely used in various industrial fields and serve as effective corrosion-resistant coatings. However, their performance in complex high-temperature, high-humidity corrosion environments remains to be evaluated. This study selected four mature corrosion-resistant coating systems from different manufacturers as test samples (MN-1 to MN-4) and prepared four test panels according to the coating requirements of each system. Concurrently, methods for pore analysis, corrosion resistance testing, and durability assessment of corrosion-resistant coatings were designed, forming the primary experimental research methods. The changes in the adhesion resistance to chlorine, sulfate ions, and carbon dioxide ions of the coatings on the surfaces of MN-1 to MN-4 under high-humidity conditions were compared to evaluate the overall corrosion resistance performance of the four coatings. Based on the corrosion resistance capabilities of the four coatings, a polymer sealant was prepared using a combination of raw materials. The six samples of the designed polymer sealant maintained an overall material weight within the range of 0.025–0.035 g under high-temperature and humid conditions, demonstrating strong resistance to aging.