Corrosion behaviour of carbon steel in Beibu Gulf tidal zone

Corrosion behaviour of carbon steel (CS) exposed in the tidal zone of Beibu Gulf was investigated by experimental method. Q235 CS specimens were designed and exposed for 12 months. The corrosion mechanism of CS was characterised by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-Ray diffraction (XRD). Results show that the corrosion performance of CS can be verified by the formula D = atn. The corrosion products are mainly composed of α-FeOOH, γ-FeOOH, β-FeOOH, Fe3O4 and γ-Fe2O3. Significantly, Cl– is an intermediate in the corrosion process and promotes the formation of the characteristic product β-FeOOH.