Development and validation of coupled erosion-corrosion model for wear resistant steels in environments with varying pH

Erosion-corrosion, the combined loss of material due to combined effects of particle erosion and electrochemical corrosion, has due to its complexity largely evaded modeling efforts. Assessment of the synergy between erosion and corrosion leading in extreme conditions to far greater material losses than for the mechanisms individually has proven elusive. Various analytical and semi-empirical approaches have been proposed with varying degree of success, but it has been a typical outcome that the predictive capabilities or transferability of such modeling efforts have been less than desirable. In current work this aspect is addressed and improvement is seeked by introducing a concept merging computational fluid dynamics (CFD) and the point defect model (PDM) to a micromechanical finite element (FE) formulated wear model. The implemented approach is utilized to study erosion-corrosion in a stirring tank configuration where flow velocity, abrasive particle type, solution chemistry, temperature and pH are varied. In order to investigate model performance experimental work supplemented by a detailed characterization regime is performed to produce a dataset for model validation for a wear resistant steel with two different abrasives, quartz and chromite particles. The respective experiments indicative of industrially relevant erosion-corrosion conditions are modelled and the Results are directly compared to model predictions. The erosion-corrosion model is found to produce satisfactory results in relation to the validation tests and predict the main trends of the experimental dataset appropriately. The capabilities and approximations underlying the introduced erosion-corrosion model are evaluated, discussed and future development needs identified.