EFFECTS OF PARTICLE-VELOCITY AND APPLIED POTENTIAL ON EROSION OF MILD-STEEL IN CARBONATE BICARBONATE SLURRY/

The present paper describes a study of the combined effects of velocit y and applied electrochemical potential on the erosion of mild steel i n an aqueous carbonate/bicarbonate slurry. The erodent used was alumin a; the velocity was varied between 2 and 10 m s(-1) and the potential between -1.0 and 0.2 V (saturated calomel electrode). Measurements wer e made of the erosion rate in the absence of corrosion (when the surfa ces were cathodically protected), the instantaneous corrosion rate, an d the overall erosion-corrosion rate. The results showed that the effe ct of velocity varied as a function of the applied potential. Velocity exponents were evaluated for the various erosion-corrosion conditions , and the tends in the variation of the exponents were discussed for e ach of the applied potentials. Criteria for the existence of erosion-c orrosion regimes in aqueous environments were suggested, and were used to generate an erosion-corrosion map based on the experimental data. (C) 1996 The Institute of Materials.