IDENTIFICATION OF TRANSITIONS IN EROSION-CORROSION REGIMES IN AQUEOUSENVIRONMENTS

Wastage of materials due to the synergistic effects of erosion and cor rosion occurs in both ''dry'' and ''wet'' industrial processes. In the ''dry'' case, degradation occurs due to the impact of solid particles on corroding surfaces at elevated temperatures. In the ''wet'' case, wastage is due to the impact of solid particles in aqueous media or ot her reactive liquids. A distinctive difference between the investigati ons in these two research areas is in the various attempts made to ass ign ''regimes'' of behaviour. In the ''dry'' high temperature studies, there have been attempts to define possible regimes of behaviour. How ever, in the ''wet'' environments, this has not generally been the cas e. This paper describes the initial results from an experimental progr amme which aims to identify and explain transitions in erosion-corrosi on ''repimes'' at room temperatures, for pure metals and alloys. It wi ll be shown how such results can be used to define erosion-corrosion r egimes in such environments, which has not been attempted to date. In addition, an aqueous erosion-corrosion map is proposed where the trans itions between the aqueous erosion-corrosion regimes is given as a fun ction of erodent velocity and potential.