Enhanced mechanical properties in β-Ti alloy aged from recrystallized ultrafine β grains

Ultrafine beta grain structures with recrystallized morphologies were fabricated by severe plastic deformation and subsequent annealing in Ti-10Mo-8 V-1Fe-3.5Al alloy. The minimum mean beta grain size of 480 nm was obtained for the first time as a recrystallized structure in Ti alloys. Precipitation behavior of alpha in subsequent aging significantly changed with decreasing the recrystallized beta grain size. Both tensile strength and total ductility of the aged Ti-alloy were increased by the beta grain refinement. Tensile strength of 1.6 GPa and total elongation of 9.1% were achieved in the aged specimen having the prior beta grain size of 480 nm, which was attributed to its finer and more homogeneous precipitated microstructure having a mixture of nanoscale thin-plate a and globular alpha without side a plates along beta grain boundaries. (c) 2020 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).