Influences of Varying Current by Tungsten Inert Gas Welding and its Process Parameters on Weld Quality of AA 6061 Aluminium Alloy

Abstract

An extensively studied Al-Mg-Si (AA6061) alloy has been considered for this investigation. This alloy is used for large number of industrial applications since it possesses medium to high strength to weight ratio, excellent weldability and corrosion resistance. It has been observed that these alloys are usually used in sheet form and were welded for large application. Even though a number of welding procedures are available, the most convenient and economical procedure of tungsten inert gas (TIG) welding was used to weld Al-Mg-Si sheets. All the sheets were having a thickness of 3.0 mm. In the case of single pass TIG welded samples, the pulsed current has been found beneficial as it is most advantageous over the conventional continuous current process. The use of pulsed current parameters has been found to improve the mechanical properties of the welds compared to those of continuous current welds of this alloy. This is possibly due to the grain refinement occurring in the fusion zone. These results clearly demonstrated that current parameters and its optimization is most important aspect for obtaining a good weldment. An Influence of process parameters and their influence on mechanical properties are explained in detail in light of microstructural details.