A Review: Parametric effect on mechanical properties and weld bead geometry of Aluminium alloy in GTAW

Abstract

Gas tungsten arc welding (GTAW) is high quality and high precision welding process which are suitable for welding thin metals. Inert gas as helium and argon are used as a shielding gas to prevent the weld bead from air, dust and other contaminations in welding. There are so many welding process parameter affect the weld quality in GTAW. Important process parameter which mainly affect the weld quality are welding current, arc voltage, welding speed, gas flow rate, heat input, gun angle, stand of distance and specimen thickness. Important quality parameters in GTAW process are depth of penetration and weld bead geometry. Depth of penetration and weld bead width both are affected by welding speed. As welding speed increases, depth of penetration increases but weld bead width decreases. The weld joint quality can be assessed in terms of weld bead geometry, mechanical properties and distortion. Post weld heat treatment is done to improve the weld quality by solutioning and aging which results in refinement of grain size and thus, mechanical properties of weld joint improved. Heat input effects the filler rod deposition rate in the form of droplets in weld bead. This paper covers review of process parameters of GTAW and their effect on weld quality.