Journal of Materials Research and Technology (May 2021)
A study on corrosion of X80 steel in a simulated tidal zone
Abstract
In the paper, an experimental technique simulating tidal rhythm for studying the tidal zone corrosion of metals was developed and the tidal zone corrosion of X80 pipeline steel was studied via the technique using weight loss, electrochemical measurement, X-ray diffraction (XRD), and scanning electron microscope (SEM). The results showed that the corrosion rate and corrosion current density (icorr) of the steel increased with the steel's altitude in the tidal zone. No obvious pit was observed on the steel surface after 60 tidal cycles in the seawater, indicating that uniform corrosion and non-uniform corrosion dominated the tidal zone corrosion of the steel in the work. The corrosion products in the full immersion zone were mainly Fe3O4 and γ-FeOOH, with the additional corrosion product of Fe2O3 detected in zones above the full immersion zone. The mechanism of tidal zone corrosion of the steel and the formation evolution of the corrosion products were also discussed in the paper.