Erosion-corrosion

Abstract

Generally, almost all components moving near a corrosive fluid hitting the material surface are exposed to corrosive erosions. Meanwhile, transmission pipes of gas, oil, and water, the transmission lines of corrosion fluid in the industrial reactor, and heat exchange systems are suffering significantly from the erosion-corrosion phenomenon. Erosion-corrosion can generate material loss much greater than the sum of the pure erosion and the pure corrosion individually due to the interaction between them. Erosion-corrosion in aqueous systems is dominated by two major mechanisms: electrochemical corrosion and mechanical erosion. On account of the greater material loss than the sum of their components, the interaction between electrochemical and mechanical processes has been recognized in many works, and they have been referred to as “Synergistic” and “Additive” effects. The so-called synergistic effect is normally used to describe how corrosion can enhance erosion, while the so-called additive effect refers to the mechanism by which erosion can enhance corrosion. In general, the influencing parameters in this process include: the solid sand particles (mass, hardness, density, size, shape, velocity, and impact angle), target material (hardness, metallographic structure, strength, ductility, and toughness), and the environment (slurry composition, flow velocity, and temperature).