TWI

A thermal numerical 3D model to predict temperature and machine torque values for bobbin tool friction stir welding (FSW) is presented. The model includes a 3D representation of the work piece, clamping and bobbin tool. The heat transported by the tool's rotation and the material in the shear layer around the tool are considered using convective flow in an Eulerian frame by implementing a fast analytical shear layer model that accounts for the material motion around the tool. The shear layer model is calibrated with the output of a CFD model of the material flow around the tool. A TPM heat source model which governs heat generation by a pseudomechanical source is described. The 3D moving geometry model's output includes thermal history of the weld as well as the predicted machine torque for a given set of welding parameters. The transient thermal field prediction were validated experimentally for AA2024 sheet, thickness 4 mm.

8th International Symposium, 18-20 May 2010, Session 5B: Modelling 2, Paper 02