TWI

The results of two testing programmes dealing with the metallurgical and mechanical properties of friction stir weldments (thickness 6 and 25 mm) in the aluminium alloys 2024, 5083, 6082/6060 and 7075 are reported, and a systematic study of the key welding variables (tool rotational speed and tool feed per revolution) is presented. Issues discussed include: the drop in hardness in the weld region and its dependence on welding variables; transverse tensile testing results (ultimate tensile strength); microstructural analysis (including grain structure within the nugget zone and thermomechanically affected zone); toughness properties evaluated from three-point bend tests; and fatigue testing of friction stir butt joints.

5th International Symposium, 14-16 Sep 2004, Session 6B: Mechanical Properties, Paper 03