TWI

The viscoplastic behaviour of two aluminium alloys (non heat-treatable AA5083-H111 and heat-treatable AA6082-T6) was analysed by performing tensile tests at different temperatures and strain rates and the friction stir weldability of the materials investigated at varied welding conditions using different FSW tools and welding parameters. The relationship between the material flow during FSW and the plastic behaviour of the materials was investigated in order to clarify the influence of plastic behaviour on friction stir weldability. Plates of 6 mm thickness were used in the experiments. Tensile tests were conducted at testing speeds of between 5 and 3000 mm per minute and temperatures between 25 and 500 deg.C. The same tool geometry was used in all welding tests, although the pin diameter, shoulder diameter, pitch angle, tool speed, rotational speed and vertical load were varied. Samples were visually inspected for defects after welding. Tensile stress-strain curves are presented at different temperatures in order to illustrate the evolution of the flow stress with plastic deformation and temperature.

8th International Symposium, 18-20 May 2010, Session 3A: Modelling 1, Paper 02