Corrosion behavior of low-alloy steel in tidal zone: A simulated investigation

Abstract

Corrosion behaviors of low-alloy steel were investigated in the simulated tidal zones using stereoscopic microscope, field emission scanning electron microscope, X-ray diffraction, open circuit potential, and electrochemical impedance spectroscopy. The result shows that the corrosion in various tidal zones is much more severe than that of the immersion (IM) zone, and more severe corrosion takes place in the low tide (LT) and middle tide (MT) zones compared with the high tide (HT) zone. In the present test-time scale, uniform corrosion predominantly occurs in the IM and LT zones, and non-uniform corrosion occurs in the MT and HT zones. The main corrosion products in the LT and MT zones are Fe3O4 while α-FeOOH dominates the composition of rust layers in the HT zone.