The aim is to analyze a junction produced by a Friction Stir Welding (FSW) joining process under multiaxial loading, employing a modified Arcan test that allows an angle variation of the loading in order to evaluate the failure of the FSW weldment as compared to the base material. A short review of the earlier studies and relevant theories about the FSW processes and fracture modes I and II under multiaxial loading are presented and were experimentally evaluated for an AA2024-T3 aluminum alloy sheets (t = 1.6 mm) processed by FSW. The results obtained can serve as a basis to compare the junctions made using FSW and conventional joint methods such as rivets (very common practice in the aeronautical industry).
The hardness of AA 2024 is mainly dependent of the precipitation state in the material. This one will vary through the process of friction stir welding (FSW) which generates heat and deformations. The most important effect will be the thermal excursion which greatly affects the nature and the distribution of precipitates and so the mechanical properties of the material. Three Myhr & Grong-type submodels have been used in this study in order to simulate the variation of hardness in AA 2024-T3 FSW welds. These models allowed to simulate the hardening by growth of S-precipitates and the softening by coarsening and dissolution of GPB zones / co-clusters or S-precipitates. Finally, the natural ageing was taken into account following the Robson model. The complete model has been calibrated with isothermal data found in the literature and still has to be optimised. Nevertheless, preliminary results show the coherence of the model when performed on isothermal data. The model has been also applied to predict FSW hardness profiles that are compared to those found in the literature.
As a relatively new solid-state joining process, friction stir welding (FSW) may provide a feasible approach to join dissimilar materials such as Mg to Al alloys. In this work, the effects of selected process parameters including work-piece placement, pin tilting angle, and pin location on the quality of dissimilar AA 2024-T3 to AZ31B-H24 butt joints were investigated for the first time. Sound butt joints with low distortion and no solidification cavities or cracks were successfully obtained indicating the potential of FSW to join dissimilar Al to Mg alloys.
Mathematical modeling of changes in temperature distribution during friction stir welding in massive samples