Erosion Corrosion of Carbon Steel in Aqueous Slurries

Abstract

Erosion corrosion of an usual carbon steel in a variety of aqueous slurries of 10% Al₂O₃ powder composed of 0.1M NaOH, concentrated cooling water (synthetic rather than natural), 3% NaCl, and 0.01M HCl was investigated from the electrochemical point of view. The total weight loss, W_t, was experimentally divided into the following three terms: the mechanical loss, W_m, the corrosion loss, W_c, and the loss due to erosion corrosion, W_ec. W_m was measured under catholic polarization whereby no corrosion occurred. On the other hand, W_c was obtained in the respective solutions free of alumina powder. Therefore, W_ec was evaluated as the difference between W_t and the sum of W_m and W_c. Of these, W_m was relatively small compared to other factors under the experimental conditions employed. The weight loss due to corrosion associating with erosion, i.e., W_c+W_ec, was discussed from the electrochemical concept.