Browsing by Author "Lee, Lucie Alexandra"

Now showing 1 - 2 of 2
  • Thumbnail Image
    ItemOpen Access
    2D linear friction weld modelling of a Ti-6Al-4V T-joint
    (Technological Educational Institute of Eastern Macedonia and Thrace, 2015) Lee, Lucie Alexandra; McAndrew, Anthony; Buhr, Clement; Beamish, K. A.; Colegrove, Paul A.
    Most examples of linear friction weld process models have focused on joining two identically shaped workpieces. This article reports on the development of a 2D model, using the DEFORM finite element package, to investigate the joining of a rectangular Ti-6Al-4V workpiece to a plate of the same material. The work focuses on how this geometry affects the material flow, thermal fields and interface contaminant removal. The results showed that the material flow and thermal fields were not even across the two workpieces. This resulted in more material expulsion being required to remove the interface contaminants from the weld line when compared to joining two identically shaped workpieces. The model also showed that the flash curves away from the weld due to the rectangular upstand "burrowing" into the base plate.Understanding these critical relationships between the geometry and process outputs is crucial for further industrial implementation of the LFW process.
  • Thumbnail Image
    ItemOpen Access
    Modelling of the workpiece geometry effects on Ti–6Al–4V linear friction welds
    (Elsevier, 2015-12-15) McAndrew, Anthony; Colegrove, Paul A.; Addison, Adrian C.; Flipo, Bertrand C. D.; Russell, Michael J.; Lee, Lucie Alexandra
    Linear friction welding (LFW) is a solid-state joining process that is finding increasing interest from industry for the fabrication of titanium alloy (Ti–6Al–4V) preforms. Currently, the effects of the workpiece geometry on the thermal fields, material flow and interface contaminant removal during processing are not fully understood. To address this problem, two-dimensional (2D) computational models were developed using the finite element analysis (FEA) software DEFORM and validated with experiments. A key finding was that the width of the workpieces in the direction of oscillation (in-plane width) had a much greater effect on the experimental weld outputs than the cross-sectional area. According to the validated models, a decrease of the in-plane width increased the burn-off rate whilst decreasing the interface temperature, TMAZ thickness and the burn-off required to remove the interface contaminants from the weld into the flash. Furthermore, the experimental weld interface consisted of a Widmanstätten microstructure, which became finer as the in-plane width was reduced. These findings have significant, practical benefits and may aid industrialisation of the LFW process.