Feasibility study of FSW, LBW and TIG joining process to fabricate light combat aircraft structure

Abstract

In this research, friction stir welding (FSW), laser beam welding (LBW) and tungsten inert gas (TIG) welding are used to join precipitation hardening aluminum alloy 2014-T6. This alloy is a potential candidate in heavy structural fabrication industries due to strength ratio. However, the joining of this alloy is a major problem in assembly line. Hence, to find an ideal method for welding this alloy, three processes were compared in terms of mechanical and metallurgical properties of welded joints. Results showed that the FSW joints disclosed better strength than other LBW and TIG joints. In comparison to LBW and TIG joints, FSW conceived narrow heat-affected zone and recorded maximum hardness of 135 VHN. Similarly, the maximum hardness in the LBW and TIG welded joints were 110 VHN and 92 VHN respectively. The reason for maximum strength in FSW joints is the finer size and uniform distribution of strengthening precipitate. (Particle size diameter of 39 nm, thickness of 29 nm).

Keywords

• Friction stir welding
• AA2014-T6
• Laser beam welding
• Tungsten inert gas welding
• Strength properties