Abstract: In activated flux PAW welding, the welding arc temperature field is measured by the infrared sensing and computer image technique. The distribution models of welding arc heat flow density of activated flux PAW welding are developed. The phenomenon of welding arc effecting by activated flux is studied, and the relationships between the welding arc voltage and activated flux is studied. The results show that the welding arc temperature distribution in activated flux PAW welding is compact, the outline of the welding arc temperature field is narrow, the range of the welding arc temperature distribution is concentrated, the welding arc radial temperature gradient is large, the welding arc radial temperature gradient shows normal Gauss distribution, the activated flux PAW welding arc is contractive, the arc tail is disappear, the efflux plasma is increasing, the force of penetration is strengthening, the arc voltage is larger.

Key words: Activated flux PAW welding, Temperature field, Welding arc