Evaluation of mechanical properties and load carrying capabilities of Riveted and TIG welded joints of aerospace grade material /
Muhammad Talal Shahid
- 133p. Soft Copy 30cm
Aluminum alloys such as Al 5052-H32 are widely used in the aerospace industry due to their excellent corrosion resistance, moderate strength, and good weldability. In this research, a comparative investigation was conducted on riveted and TIG-welded lap joints made from Al 5052-H32 to assess their mechanical performance and microstructural characteristics. TIG welding, performed using ER4043 filler wire, was explored as an alternative to traditional riveting in non-structural aircraft components such as access panels, enclosures, and ventilation systems. Tensile testing revealed that welded joints exhibited superior strength, with failures consistently occurring in the base material rather than the joint, indicating strong fusion integrity. In contrast, riveted joints failed through separation of the rivet head, highlighting a limitation in their loadbearing capacity. Microhardness testing and optical microscopy were used to analyze the fusion zone (FZ), heat-affected zone (HAZ), and base material (BM) in welded joints, as well as the regions adjacent to rivet holes. Results showed increased hardness in both the FZ and HAZ, attributed to localized grain refinement and solidification effects from the welding process. In riveted joints, slight hardness variations were observed near the rivet due to compressive plastic deformation. The microstructure images confirmed the presence of partially recrystallized grains in the HAZ and fine equiaxed grains in the FZ. These findings demonstrate that TIG welding can offer mechanically superior and metallurgically favorable joints for selected aircraft applications, provided that design constraints and service conditions are appropriately considered.