Corrosion Behavior of Galvanized Steel for Porcelain Insulator’s Pin in HVAC Transmission Line

Abstract

The corrosion behavior of galvanized steel in corrosive media of simulated concrete pore solution (SPS) with and without NaCl has been studied for applying it to porcelain insulator’s pins in high-voltage alternating current (HVAC) transmission line. It was found that zinc coating of galvanized steel was corroded increasingly for the first 3 days corrosion test in SPS mixed with NaCl solution. After that the passive layer was formed on the surface of galvanized coating and consequently, the corrosion rate was dramatically decreased nearly five times of initial corrosion rate after 21 days. In this experiment, the investigations have been performed by SEM, optical microscope and visual observation. The results show that this compact and well adherence passive layer can be effectively hindered the corrosion process.