AN INTRODUCTION TO ACTIVATED TIG WELDING - PRODUCTIVE WELDING PROCESS

摘要

The use of activating fluxes provides a novel method of increasing the penetration capability of the arc in GTA welding. The process is effected through the application of a thin coating of an activating flux material onto the joint surface prior to welding. The effect of the flux is to constrict the arc which increases the current density at the anode root and the arc force action on the weld pool. The constricted arc produces a narrow deep weld compared with the wide shallow weld bead obtained with conventional GTA. Activating fluxes are available commercially for welding a range of materials, including C-Mn steel, Cr-Mo steels, stainless steels, aluminium and its alloys, titanium and its alloys and nickel based alloys. The fluxes are generally available in the form of either an aerosol or as a paste (powdered flux mixed with a suitable solvent, e.g. acetone or isopropanol) which is applied to the surface with a brush.