Work

Sustainable manufacturing of a high-value tubular Ti–6Al–4V component using flow-forming process; effect of feed-rate on microstructure evolution

Year: 2025

Type: article

Abstract: Flow-forming is a comparatively sustainable manufacturing process with a potential to produce seamless high-value tubular components (e.g., actuators and shafts). The 3D nature of localised deformation and hence the triaxial stress-state occurring during this process necessitates comprehensive understanding of the underlying microstructural deformation mechanisms. This paper investigates microstructure evolution and the corresponding deformation mechanisms during warm (i.e., pre-heated to 600 °C) flow-forming of Ti-6Al-4V alloy under different feed rates. The increase in the feed-rate, from 1 to 2.5 mm/rev, which results in an increased roller-workpiece contact area, had led to longer final component (i.e., from 53 to 108 mm). EBSD analyses of microstructure suggest the occurrence of dynamic recrystallisation (DRX) in both α and β phases. Elongated α grains were observed in the outer surface, indicative of severe plastic deformation, accommodated by the deformation of the primary α grains and continuous dynamic recrystallisation (CDRX) in β. Analyses of crystallographic texture show the presence of strong B-fiber shear texture, indicating dominant shear deformation. The calculated Schmid factor values confirmed the dominant activation of both prismatic and pyramidal slip systems during the forming process.

Source: Materials Chemistry and Physics

DOI: 10.1016/j.matchemphys.2025.131086