A METHODOLOGY FOR THE CONSTRUCTION OF THE EROSION-CORROSION MAP IN AQUEOUS ENVIRONMENTS

For the erosion of alloys under aqueous conditions, there have been so me recent attempts to identify the transitions between the erosion-cor rosion regimes using laboratory results. Such transitions can be super imposed on an erosion-corrosion map as a function of the main corrosio n and erosion variables. Defining the magnitude of the wastage rate on such maps enables the relevant process parameters involved in the dam age process to be optimized. The object of this work was to model the erosion-corrosion behaviour of mild steel exposed to an aqueous soluti on containing alumina particles. The results were used to identify the transitions between the erosion-corrosion regimes on erosion-corrosio n mechanism maps. Process control maps, which show the magnitude of th e wastage rate, were also constructed using such an approach. This pap er describes the basis of the mathematical models used to construct th e boundaries on the maps. The effects of particle size, flux, and solu tion pH on such boundaries are demonstrated. In addition, a qualitativ e comparison is made between the results of the model, and a series of slurry erosion-corrosion tests of mild steel in aqueous media. (C) 19 97 Elsevier Science S.A.