This paper firstly provides an overview of major efforts made over the past several decades on developing the test apparatus for the study of erosion-corrosion of ferrous-based steels. The merits and the application range of the set-ups, i.e., rotating disc/cylinder electrode system, slurry jet impingement rig, and test flow loop, are introduced. Secondly, the advantages and limitations of both non-electrochemical and electrochemical methods used for the measurement of erosion-corrosion are presented. Thereafter, the interaction between erosion and corrosion using a cyclic erosion-corrosion method was introduced. The synergy between erosion and corrosion for the steels under the passive state were analyzed on the basis of the breakdown and restoration of the passive film. In addition, the difference between the obtained erosion-enhanced corrosion and the corrosion-enhanced erosion using different experimental methods for steels under active corrosion was discussed. Finally, the interaction between the localized corrosion and erosion was studied through the dynamic change of the local current distribution revealed by the wire beam electrode.

In this work, flow accelerated corrosion (FAC) and erosion−corrosion of marine carbon steel in natural seawater were electrochemically studied using a submerged impingement jet system. Results show that the formation of a relatively compact rust layer in flowing natural seawater would lead to the FAC pattern change from ‘flow marks’ to pits. The increase of the flow velocity was found to have a negligible influence on the FAC rate at velocities of 5−8 m s−1. The synergy of mechanical erosion and electrochemical corrosion is the main contributor to the total steel loss under erosion−corrosion. The increase of the sand impact energy could induce the pitting damage and accelerate the steel degradation. The accumulation of the rust inside the pits could facilitate the longitudinal growth of the pits, however, the accumulated rusts retard the erosion of the pit bottom. The erosion and corrosion could work together to cause the steel peeling at the pit boundary. The steel degradation would gradually change from corrosion-dominated to erosion-dominated along with the impact energy increasing.

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The corrosion performances of the EH 36 carbon steel in stagnant and flowing natural sea water and synthetic sea waters were investigated. Results show that the general corrosion rates of the steels are close in stagnant natural sea water and synthetic sea waters. The corrosion rate, corrosion feature and the rust components of the steels in flowing 3.5% NaCl solution were significantly different from those of the steels in flowing natural sea water, indicating 3.5% NaCl solution could not restore the flow accelerated corrosion (FAC) performance of carbon steels in marine environment. The pH difference between 3.5% NaCl solution and natural sea water is not the main contributor for FAC performance changing. The corrosion performance of the steel in ASTM D1141 synthetic sea water was similar to that in natural sea water within small deviations of the corrosion rate at both static and flowing conditions.