Research on the Corrosion Mechanism of Carbon Steel Under AC and DC Electric Fields

Transmission lines and towers are exposed to complex and harsh environments for long periods, suffering from electrochemical corrosion, oxidation corrosion and other effects, leading to equipment damage and deterioration. In order to study the corrosion issues of metal equipment in power systems, this Research investigated the corrosion mechanism of carbon steel under the influence of AC and DC electric fields, particularly focusing on the corrosion issues of metal equipment in the hot and humid environment of southern regions. Through accelerated laboratory tests, the corrosion products and their evolution patterns of carbon steel under AC and DC electric fields were analyzed. We employed present multiple material analysis methods, including X-ray diffraction (XRD), scanning electron microscopy (SEM), and electrochemical testing, systematically characterizing the corrosion behavior of carbon steel in a simulated marine atmospheric environment. Electrochemical test results showed that the application of an electric field significantly accelerated the corrosion process of carbon steel, with the corrosion effect being most pronounced under the DC electric field. The Research also explored the formation of corrosion products and their impact on the corrosion rate. Results from XRD and SEM revealed the cause of the electric field-enhanced corrosion effect, namely the electric field-induced directional movement of chloride ions (<tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\text{Cl}^{-}$</tex>) accelerating the corrosion process.