Microstructural characterization of Ti–6Al–4V machining chips after remelting and severe deformation

The present work was initiated to recycling the machining chips of Ti–6Al–4V alloy as part replacement of titanium sponge and expensive alloying materials for manufacturing Ti-alloy ingots. The technology includes a two-step processing route involving an initial remelting of machining chips into ingot by vacuum-induction melting furnace followed by conversion of the ingot into slab by severe hot working processes (forging and large strain hot rolling). Optical microscope was used to investigate the microstructures. The results show that when deformation process is carried out in the α + β-phase field, a much finer α + β-structure can be obtained, because the primary α-phase limits the growth of the β-phase. Both the primary α-phase and β-phase deform simultaneously and the β grains are easier to recrystallize.