The Electrochemical Behavior of A508III Low Alloy Steel in Simulated Pressurized Water Reactor Primary Water Solutions

Abstract

The corrosion and electrochemical behavior of A508III low alloy steel in boric acid solutions with or without LiOH at 25 °C and 70 °C were studied by weightloss measurements and electrochemical measurements. Depending on the solution composition and the resultant pH, A508III low alloy steel could be in active dissolution state or in passive state. These results were consistent with the potential-pH diagram. Increasing temperature or boric acid concentration of solutions accelerated the corrosion rates and electrochemical processes. Corrosion rates decreased with the addition of LiOH. Adding LiOH in H3BO3 solutions increased the current densities at relatively high anodic potentials, which had a complex effect on electrochemical impedance spectroscopy.