Texture evolution in h.c.p. (α) phase derived from aging of a differently processed metastable b.c.c. (β) titanium alloy was investigated. The study was aimed at examining (ⅰ) the effect of different b.c.c. cold rolling textures and (ⅱ) the effect of different defect structures on the h.c.p transformation texture. The alloy metastable β alloy Ti-10V-4.5Fe-1.5A1 was rolled at room temperature by unidirectional (UDR) and multi-step cross rolling (MSCR). A piece of the as-rolled materials were subjected to aging in order to derive the h.c.p. (α) phase. In the other route, the as-rolled materials were recrystallized and then aged. Textures were measured using X-ray as well as Electron Back Scatter Diffraction.Rolling texture of p phase, as characterized by the presence of a strong y fibre, was found stronger in MSCR compared to UDR, although they were qualitatively similar. The stronger texture of MSCR sample could be attributed to the inhomogeneous deformation taking place in the sample that might contribute to weakening of texture. Upon recrystallization in β phase field close to β-transus, the textures qualitatively resembled the corresponding β deformation textures; however, they got strengthed. The aging of differently β rolled samples resulted in the product α-phase with different textures. The (UDR + Aged) sample had a stronger texture than (MSCR + Aged) sample, which could be due to continuation of defect accumulation in UDR sample, thus providing more potential sites for the nucleation of a phase. The trend was reversed in samples recrystallized prior to aging. The (MSCR + Recrystallized + Aged) sample showed stronger texture of a phase than the (UDR + Recrystallized + Aged) sample. This could be attributed to extensive defect annihilation in the UDR sample on recrystallization prior to aging. The (MSCR + Aged) sample exhibited more a variants when compared to (MSCR + Recrystallized + Aged) sample. This has been attributed to the availability of more potential sites for nucleation of a phase in the former. It could be concluded that a transformation texture depends mainly on the defect structure of the parent phase.
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