Numerical Modelling of the Plasma Discharge During Electron Beam Welding (EBW)

D. Trushnikov[1], G. Mladenov[2]
[1]Perm National Research Polytechnic University, Perm, Russia
[2]Institute of Electronics of Bulgarian Academy of Sciences, Sofia, Bulgaria
Published in 2014

This work describes a model for plasma formation in the keyhole and above the EBW zone. The parameters of the plasma are closely connected to the characteristics of the thermal action of the electron beam on the welded metal, which allows operational control and study of EBW. The ionization intensity of the vapour due to beam electrons and high-energy secondary and backscattered electrons is calibrated using the plasma parameters when there is no polarized collector electrode above the welding zone. It is shown that there is a need to consider the effect of a strong electric field in the crater near the crater wall on electron emission (the Schottky effect) when calculating the current of a non-independent discharge.