At present

the major power systems around the world are still dominated by the form of AC synchronous grid. Due to the periodic changes in the direction of the electric field in alternating current

it is generally recognized that the influence of the alternating current field on metal corrosion products is much less than that of the direct current field. In this paper

the effect of simulated marine atmospheric corrosion environment and 400 kV/m high voltage alternating and dire

ct current on carbpn steel corrosion products are investigated by setting up a corrosion platform acpable of applying AC and DC electric fields

and the analysis and research are performed with the aid of corrosion kinetic models

corrosion product analysis

microscopic morphological analysis and electrochemical analysis methods (open circuit potential

polarisation curves

electrochemical impedance spectroscopy). The results show that the presence of an electric field will have an impact on the corrosion products. When the corrosion time is within 200 h

the corrosion product layer is thin

and such problems as bulging

pitting will occur in the corrosion product layer due to the ion directional migration and Cl

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uneven distribution because of the electric field. When the corrosion time exceeds 200 h

the corrosion product layer begins to thicken

corrosion product layering or even hardening phenomenon will appear in the DC electric field environment. While

in the AC electric field environment

the charged particles will repeatedly vibrate under the drive of the electric field force

keeping the corrosion product layer in a relatively loose and porous status.