Flow-Accelerated Corrosion Behavior of SA106 Gr. C Steel in Alkaline Solution Characterized by Electrochemical Techniques

Abstract

The activation and mass transfer processes regarding the flow accelerated corrosion of low alloy steel were studied in a de-aerated weak alkaline solution. Electrochemical techniques were applied at ambient temperature through a rotating cylinder electrode. The alkaline corrosion appeared above pH 10.4 where passive film was formed from pH 9.8 by the step oxidation and subsequent precipitation of ferrous hydroxyl compound. Such an activation process controlled the entire flow accelerated corrosion process which was identified by the analysis of velocity sensitivity of corrosion current density and limiting current density.