Erosion accelerated corrosion of a carbon steel-stainless steel galvanic couple in a chloride solution

In this work, the galvanic corrosion and erosion-accelerated corrosion of a 1020 carbon steel-304L stainless steel galvanic couple were investigated in a chloride solution using various electrochemical measurements and scanning electron microscopy observation. It was found that the average galvanic current density of the galvanic couple increases with the cathode/anode area ratio and the flow velocity of the solution. There is a synergism of galvanic corrosion and erosion of carbon steel in the flow, sand-containing solution. The percentage of the corrosive weight-loss of the total weight-loss increases with the increasing cathode/anode area ratio, indicating the accelerating corrosion of carbon steel under the large cathode-small anode geometry. Moreover, the percentage of corrosive weight-loss of the overall weight-loss decreases with the increasing flow velocity, indicating the increasing importance of erosion in the synergism of galvanic corrosion and erosion.