Effect of cadmium chloride flux in GTA welding of magnesium alloys

In the present paper, the effect of cadmium chloride (CdCl2) flux on gas tungsten welding of magnesium alloys was investigated by high speed camera, Infrared and electron probe microanalysis. The results indicated that the weld penetration with flux could be increased up to 200% of the weld penetration without flux. Infrared temperature measurement demonstrated that CdCl2 increased the arc temperature. Furthermore, high speed camera recording showed that the electric arc profile with CdCl2 was broader than that without CdCl2. The results indicated that the flux increased weld penetration mainly owing to the effects of the flux on the arc. The deionisation energy of the cation Cd2+ was higher than the ionisation energies of the dominant emitting elements in arc plasma, which could be considered as the main contribution to the weld penetration increasing with CdCl2.