erosion-corrosion
Erosion-corrosion is a class of deterioration arising when a metallic surface becomes subject to mechanical wear and corrosion of either a chemical or electrochemical nature. Fluid flow or gas movement will strip away any protective surface layers, thereby promoting corrosion of the underlying substrate. This is typically found in piping systems and turbine parts.
Key Features:
- Dual Mechanism of Damage: It results from the simultaneous action of physical erosion, such as due to fluid flow or particle impingement, and various corrosion reactions.
- Speeding Up Material Loss: The accelerated removal of protective layers from the metal surface increases the rate of corrosion and hence the loss of material, likely resulting in higher degradation rates than corrosion or erosion processes used alone.
Erosion-corrosion is one among many threats to the durability and safe service of equipment in sundry industries. In power generation, for example, it can lead to the rapid thinning of boiler tubes and the failure of heat exchanger components. In marine structures, saltwater corrosion plus wave-induced erosion may drastically reduce service life.