Classical electrical corona discharge (dielectric barrier discharge) is obtained using a generator and electrode(s) connected to a high-voltage source, a counter electrode at potential zero and a dielectric used as a barrier. That is, a high-frequency, high-voltage discharge (step-up transformer) creating a potential difference between two points requiring earth ground 35+kV and 20-25kHz. Custom electrode configurations allow for treating many different surface geometries – flat, contoured, recessed, isolated, etc. One application example is a corona discharge treating system for electrical connectors in which a combination of pin and ball electrodes concomitantly treats 3D small diameter holes and flat exterior surfaces, US Patent US5051586 (1991)2. Ozone is produced in the plasma region as a result of the electrical discharge. Corona discharge has been found to be reasonably effective at cleaning the invisible hydrocarbon materials present after, e.g., solvent or detergent washing.

Myth: Atmospheric plasma is a low-cost replacement technology for corona discharge.

Fact: Corona discharge often is more effective for treating larger surface areas and at greater surface depth. In fact, many atmospheric plasma systems are more expensive.