Mechanical Characterization of AA 6061-T6 MIG Welded Aluminum Alloys Using a Robotic Arm

Abstract

Aluminum alloys are of particular interest in the design of lightweight structures in different applications. Accordingly, welding aluminum alloys (AA) is a critical issue; for example, welding defects could arise during the traditional welding of aluminum alloys. This paper investigates the effects of welding using a robotic arm on the mechanical properties of 6061-T6 Aluminum alloy, as plates joined by Metal Inert Gas (MIG) welding. The tensile behavior and mechanical properties were investigated using tensile testing, hardness testing, and impact testing. The tensile behavior of AA-6061-T6 un-welded and welded specimens showed a decrease in the tensile strength of the welded specimens due to the fusion of the welded zone and the partially melted zone (PMZ). The hardness test showed an increase in the hardness values away from the welded zone, attributed to voids and defects in the welded and HAZ zones. In addition, the impact behavior showed that the maximum impact is in the base metal zone, and the minimum is in the HAZ. Scanning electron microscopy was used to investigate the welded and un-welded Aluminum microstructures. The mechanical properties of AA 6061-T6 Aluminum alloy were sensitive to the novel welding process.