Turkish Online Journal of Qualitative Inquiry (TOJQI) Volume 12, Issue 9, August 2021: 2311-2318

Abstract

The inspection of aluminium 6082-t6 weldments used in aircraft structures remains challenging for non-destructive testing techniques. Three longitudinal flat tensile samples were prepared, i.e., good (defect-free), defective (Lack of penetration), and without welding. Two aluminum plates of dimension 100 lengths, 120 widths, and a thickness of 8 mm were welded using Gas Tungsten Arc Welding (GTAW).  Tensile samples of overall length 200, width of the grip 20, thickness 8 mm, and 57 mm gauge length using weld plate by CNC machining. We have experimentally calculated the maximum tensile load-bearing capacity of three categories of tensile samples. Defect-free samples are subjected to gradual, incremental load to initiate and propagate weld defects. The ultrasonic inspection was adopted to study the weld defects. It identified an initiation of the flaw at 6 KN by increasing the load to 14 N defect propagated 5mm internally, and the sample sustained a maximum 21 KN load before fracture. Inline in defect sample defect propagated 3.5 mm long at a load of 11KN and sustained 18 KN load before brittle fracture. Die liquid penetrant test is used to identify defects that are open to the surface. Reference standard and validation were performed using x-ray radiography. Microstructure examinations were carried out on parent material, heat affect zone (HEZ), and weld region.