Effect of Current on the Microstructural and Mechanical Properties of Mig Welded Aa6061 Aluminum Alloy

Abstract

Aluminium and its alloy has very wide area of application i.e. aerospace, automobile and structural industries. The present investigation aimed to study the effect of MIG welding on microstructural and mechanical properties of AA6061 aluminium alloy. The characteristics of fusion zone is typical coarse columnar grains structure because of the prevailing thermal conditions during weld metal solidification. In this work, plates of 5mm thickness have been used as the base material for preparing single pass butt welded joints at different-different current values. The filler wire used for joining the plates is AA4043 (Al-5%Si by wt.) grade aluminium alloy. From this investigation, it was found that the hardness of fusion zone was degraded significantly due to usage of lower hardness filler metal. The precipitation evolution in the heat-affected zone was characterized by XRD which improves the tensile properties of the welded AA6061 alloy.