A study effect of welding process on mechanical and microstructure properties of AA5083 aluminium alloy joints

Abstract

The preset investigation is aimed to study the effect of welding processes such as MIG and TIG on mechanical and microstructure properties of AA5083 aluminium alloy. The preferred welding processes of this alloy are frequently tungsten inert gas (TIG) and metal inert gas (MIG) due to their comparatively easier applicability and better economy. In this alloy, the weld fusion zones typically exhibit coarse columnar grains because of the prevailing thermal conditions during weld metal solidification. This often causes inferior weld mechanical properties and poor resistance to hot cracking. Three sets of aluminium alloy plates with 6 mm thickness had been used as the base material for preparing single pass butt welded joints. The filler metal used for joining the plate is ER5356 for TIG and MTL 5183 for MIG of grade aluminium alloy. In the present work, tensile strength, hardness strength, bend strength, metallographic examination, Scanning Electron Microscopy (SEM) examination and salt spray test of the GMA W and GT AW joints have been evaluated, and the results are compared. From this investigation, it is found that TIG joints of AA5083 aluminium alloy showed superior mechanical properties compared with GMA W joints, and this is mainly due to the formation of finer microstructure in the weld zone.