Method and device for plasma treatment of bar or wire shaped material

摘要

In the plasma treatment of rod or fiber material the material (12) runs coaxially through a plasma nozzle (10). An Independent claim is included for equipment executing the process. The nozzle tube forms the outer electrode, working with an internal electrode (28) having a coaxial channel passing the material. Preferred features: A coating gas is supplied into the nozzle, or into the plasma (14) produced by it. The working gas in the plasma nozzle is swirled. At the outer circumference of the swirling flow of the working gas, a secondary gas is supplied into the plasma nozzle (10). An arc (38) producing the plasma is so channeled by the swirling working gas, that it winds itself helicoidally around the material (12) passing through. The material is introduced into the plasma nozzle through a guide tube (32). Inside the guide tube, pressure is reduced. It is electrically-insulating. A swirler (24) induces the swirling flow.