ACTIVATED TUNGSTEN INERT GAS WELDING OF STEEL WITH THE HELP OF FLUX INTEGRATED FILLER WIRE

Abstract

ATIG is widely used as an alternative to MP-'lIG PrOCeSS in welding of thick plates. The use of flux in the ATIG process leads to an increase in penetration as much as 300%, thereby increasing productivity and reducing manulicturing cost. Continuous research is going on to make it feasible and optimized for most of the metal. From the literature survey it was found that flux was used mainly by laying it on the weld surface after mixing with a suitable solvent. Some of the experiments also showed the positive effect on penetration by using CO2 and atmospheric air, in optimal quantity, with the shielding gas. In the present study a new method, which was so for tried only for magnesium alloy, was carried out for welding of mild steel plates. In this method the flux was introduced in the weld pooi with the help of flux coated filler wire. hO2 was used as a flux and it was coated on the filler by using the binder potassium silicate(K2SiO3). Two methods of using filler wire were tried and weld were made at different current levels ranging from 230A to 270A. Analysis of' weld cross-section revealed an increase in penetration when flux coated filler was used instead of bare filler wire. Mechanical and metallographical characterization were also conducted and it was found that welds made at 230A and 240A provided satisfactory results.