Erosion of Metals

the gradual, layer-by-layer destruction of the surface of metallic materials by mechanical action or electrical discharges (electroerosion). The erosion of metals occurs upon the frictional rubbing of surfaces, wear, and cavitation, as well as upon the action of strong gas or liquid currents upon a surface, especially at high temperatures.

Various parts of jet engines, nuclear reactors, and steam turbines and boilers are subjected to destruction by erosion. Increased resistance of parts against erosion can be achieved by improving process technology or unit design and by selecting more suitable material; heat treatment also increases resistance against erosion. Structural materials have been developed that provide durable operation of parts under erosive conditions, such as some niobium and molybdenum alloys.

Erosion processes are the basis for many types of metal treatment, such as sandblasting, shotblasting, ultrasonic treatment, and electroerosive machining (or electron discharge machining).