Corrosion Behaviors of Galvanized Steel and Stainless Steel in Soil Solutions with Different pH Values

It is one of important steps to safeguard grid safety employing more corrosion-resistant metals than galvanized steel for ground conductors. The corrosion behaviors of carbon steel in the soil solutions with different pH values were studied by means of electrochemical impedance spectroscopy and surface analysis techniques. It is found that the impedance of both galvanized Q235 steel and 304 stainless steel in alkaline or acidic soil solutions increases at the early stage and then gradually declines during the immersion course. The anti-corrosion performance of stainless steel is about ten times that of carbon steel according to ｜Z｜0.05 value of modulus of impedance. 304 stainless steel is one of potential materials for grounding electrode based on its outstanding anti-corrosion performance.