Effects of particle velocity and applied potential on erosion of mild steel in carbonate/bicarbonate slurry

Abstract

The present paper describes a study of the combined effects of velocity and applied electrochemical potential on the erosion of mild steel in an aqueous carbonate/bicarbonate slurry. The erodent used was alumina; the velocity was varied between 2 and 10m s−1 and the potential between −1·0 and 0·2 V (saturated calomel electrode). Measurements were made of the erosion rate in the absence of corrosion (when the surfaces were cathodically protected), the instantaneous corrosion rate, and the overall erosion–corrosion rate. The results showed that the effect of velocity varied as a function of the applied potential. Velocity exponents were evaluated for the various erosion–corrosion conditions, and the trends in the variation of the exponents were discussed for each of the applied potentials. Criteria for the existence of erosion–corrosion regimes in aqueous environments were suggested, and were used to generate an erosion–corrosion map based on the experimental data.MST/3364