Effects of metal vapor on electron temperature in helium gas tungsten arcs

In order to investigate the effects of metal vapor on the thermodynamic property of arc plasma in the welding process, electron temperatures in the pure helium plasma and in the helium plasma during welding in gas tungsten arcs (GTAs) were measured by using the laser scattering method. The experimental results showed that metal vapor led to a significant decrease in the electron temperature compared with that of pure helium GTA plasma. The temperature difference reached 6000 K in the arc fringe at the maximum.