TWI

In relation to the generation of oscillating process forces during friction stir welding (FSW), hypotheses covering phenomena that can lead to dynamic effects were formulated and a finite element model of the process-machine-system (containing both the FSW process and relevant parts of the machine tool) was developed to facilitate investigation of FSW dynamics. The process was modelled using a coupled Eulerian-Lagrangian formulation and the machine was modelled using discrete spring-dashpot elements. The finite element model was set up and solved with Abaqus/Explicit 6.14-3. The Johnson-Cook model was employed to describe the material behaviour of a welded 6061-T6 aluminium alloy. Welding was performed at a rotational speed of 1500 rpm, feed speed of 1500 mm/min and tool plunge depth of 0.2 mm. The establishment of a link between welding defects and process dynamics was shown to support online process monitoring systems based on force feedback data.

12th International Symposium, 26-28 Jun 2018, Session 3B: Modelling I, Paper 01