TWI

A report is presented into the challenges faced when developing thermal, thermomechanical and flow models of the friction stir welding process, such as the evolution of predictive models, a method to find the correct contact state variable, and the combination of CFD (computational fluid dynamics) and CSM (computational solid mechanics) into one formulation. The analytical heat source model and the thermo-pseudo-mechanical model are outlined, and a threaded tool model to predict stress and temperature distributions is summarised. CFD flow and heat generation models are reviewed and a pseudo-frictional flow model to account for both frictional and viscous dissipation is described. Residual stress and distortion simulation by CSM is examined, including the incorporation of material flow, frictional and plastic heat generation. Comparisons between flow patterns measured by computational tomography and those simulated by CFD and CSM are discussed.

9th International Symposium, 15-17 May 2012, Session 4B: Modelling I, Paper 01