Experimentelle Untersuchung von Staudruck- und Stromdichteverteilung im Lichtbogen des Plasma-MIG-Prozesses im unteren Leistungsbereich
Antoniou, Antonios; Reisgen, Uwe (Thesis advisor); Pfeifer, Herbert (Thesis advisor)
Aachen (2015, 2016) [Dissertation / PhD Thesis]
Page(s): 1 Online-Ressource (XIV, 130 Seiten) : Illustrationen, Diagramme
In plasma-MIG welding, the filler wire and its arc are surrounded by a thermally ionized plasma stream. A measuring method to determine the distribution of the current density at the arcing end of the workpiece surface was developed in this thesis. By overlaying the distributions of the current density and the stagnation pressure, which was measured with an appropriate device, the interaction of current and gas flow in the plasma-MIG arc and their influence on the penetration geometry was investigated. The current density at the perimeter of the ring from the plasma electrode is not evenly distributed and the local area of the maximum current density varies according to the shielded gas flow. The profiles of current density and penetration of Plasma-MIG arc are flatter than those of the MIG arc. This is due to the plasma stream and the lateral current discharge from the filler wire. A concentration of current density at the middle of the arc can be achieved if the MIG-current or the total current is increased or if the plasma gas flow is decreased. A reduction of the shielded gas flow enlarges the arcing end. The penetration profile is deeper at locations with higher current density and stagnation pressure.