| Abstract Scope |
This work compares the effect of material flow in friction stir welds using standard and the Bobbin FSW tools, and the effect on micro-mechanical behaviour and static properties of aeronautical alloy AA6082-T6 Friction Stir Welds respectively. The bulk unidirectional flow of the standard tool FSW gave lesser thermal input and toughened mechanically worked grains lead to possible high weld efficiency (66-99%) and mechanical properties (160 to 289.87MPa UTS, 181 to189MPa 0.2% Proof Stress, 3-9.9 Stain-to-Failure), but inter-onion rings alumina, internal cracks and root flaws reduced ductility and produced premature failure. The bulk multi-directional material flow due to two adjacent rotating shoulder generated higher heat, slightly larger grains and no-root flaws in Bobbin Tool FSW plates, which made the mechanical properties (204.70MPa UTS, 126MPa 0.2% Proof Stress, 4.8 Strain-to-Failure) and predictable 70% weld efficiency. Excellent bending strength and ductility prevented premature failure. |