Number Density Distributions of Metal Vapor in Helium Gas Tungsten Arcs

Abstract

In order to investigate effects of metal vapor on the plasma state in welding process, electron temperature in helium Gas Tungsten Arc (GTA) plasma during welding was measured by using the laser scattering method. Furthermore, number density distributions of metal neutrals and ions were also measured by using the spectroscopic analysis. Our results showed that plasma during welding consisted of two plasma regions, namely, pure helium plasma region and quasi-metal plasma region.

Dynamic analysis of droplet transfer in gas–metal arc welding: modelling and experiments

“…Both modelling and experimental activities play an important role in the optimization of GMAW: the first highlights fundamental processes occurring during metal transfer, which can give insights into the optimal design of the experiments [7][8][9][10]; the second is essential to test several combinations of operating conditions and to check the overall quality of the process, for instance the insurgence of welding sputter [11][12][13][14][15][16][17][18][19]. Thermofluid-dynamic modelling plays an important role in understanding the relative importance of different operating conditions of GMAW and in highlighting physical phenomena acting during metal transfer (Lorentz forces, surface tension, plasma fluid dynamics, metal vapour diffusion, etc) [20][21][22][23][24][25].…”