With atmospheric plasma spraying, a constricted arc with high power density burns between a rod-shaped, centrically arranged tungsten cathode and a ring-like, water cooled copper anode. This arc gives a majority of its heat energy to the gas, which ionizes (Ar, He) or, with two atomic gases (H2, N2), first dissociates before being ionized. With recombination, the absorbed heat energy is released again and an electrical neutral plasma flame leaves the anode at high speed and with a high temperature between 3,000 K and 30,000 K. With this process all metals, high melting oxides, carbides and silicides can be melted and sprayed. A precondition, however, is to use materials that do not decompose or completely evaporate in the plasma flame. 

With the help of a carrier gas, the coating material in powder form is blown inside or outside the burner into the plasma flame, where it melts and is sprayed with high velocity onto the pre-treated surface of the substrate to be coated.

Since the dwell time of the powder in the plasma is located in the microsecond range and the different spraying materials must melt on, the prescribed grain sizes of the powders have to be adhered to in narrow tolerances.