27 May 2021

Plasma Spray Coating – Overview

By ruiiid5

Thermal Plasma Thruster is a relatively new generation of direct-fire spraying equipment. It works on the same principle as that of a traditional steam rocket nozzle, but instead of being fed with gaseous fuel and ignited by an external source, it is ignited directly by an electric arc. The resulting combustion products have very high temperatures and are extremely effective in high-speed direct-fire applications.

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This makes them ideal for applications requiring extremely high firing speeds and/or diameters, where traditional thrusts would not be appropriate. They can also achieve greater accuracy than their counterparts because their smaller size does not compromise the efficiency of the spray.


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The principle of the Thermal Plasma Spray, like that from Poeton is similar to that of the more familiar hot gas nozzle, in that an electrode is laid over the conductive medium (typically an inert gas) and the droplets of gas are emitted from the nozzle in very hot, ionized plasma streams. Because the droplets do not have a way of making their way down the electrode, they form a blanket around the electrode, protecting it from the corrosive effects of the electrolyte.

The size of the droplets is typically very small, up to a few micrometers in diameter, which gives them high energy output but low density. With such high firing rates, these properties make them highly effective in applications requiring high firing rates and/or diameters, where greater accuracy is essential.