Galvanic effect of magnetite on the corrosion behavior of carbon steel in deaerated alkaline solutions under flowing conditions

•The effect of magnetite on the corrosion of carbon steel under flowing conditions is provided.•The magnetite specimen was prepared using the electrodeposition method.•Carbon steel acted as an anode of the galvanic couple with magnetite.•The galvanic coupling with magnetite increased the corrosion rate of carbon steel. The effect of magnetite on the corrosion of carbon steel was investigated in simulated secondary water of pressurized water reactors at 60°C by using the immersion and electrochemical tests. The corrosion rate of carbon steel was increased by the galvanic coupling with magnetite, and was more accelerated with increasing the area ratio of magnetite to carbon steel. From the electrochemical behavior of carbon steel and magnetite, it was verified that the corrosion of carbon steel is accelerated by a galvanic corrosion mechanism. This phenomenon is expected to be an acceleration factor on the corrosion of carbon steel piping.