Mechanical response and effects of Β-to-α" phase transformation on the strengthening of Ti-10V-2Fe-3Al during one-dimensional shock loading

Plate impact experiments and quasistatic reload compression tests were conducted on a typical metastable Β-titanium alloy, Ti-10V-2Fe-3Al, to investigate its mechanical response and strengthening behavior under one-dimensional shock-loading conditions. The Hugoniot elastic limit (HEL) for this alloy was measured to be 2.89GPa using a velocity interferometer (VISAR). The shock Hugoniot was also determined by measuring the stress, shock, and particle velocity as independent variables using manganin stress gauges. The fitted shock parameters (C₀ and S) of Ti-10V-2Fe-3Al were found to be nearly identical to those of the α+Β-titanium alloy Ti-6Al-4V. However, the measured Hugoniot in the stress-particle velocity space lied slightly above that of Ti-6Al-4V due to the higher density of Ti-10V-2Fe-3Al. The results of the quasistatic reload compression tests show that the postshock Ti-10V-2Fe-3Al is strengthened. The martensitic (Β-to-α") phase transformation during shock wave loading may play a crucial role in the strengthening of this alloy. Finally, the inflection point corresponding to the phase transition was not observed in the VISAR trace even though the occurrence of the Β-to-α" phase transformation was confirmed by microstructural analyses. The unobserved inflection point can be attributed to the difficulty in resolving the break of the wave fronts due to a very small or no change in the specific volume resulting from the martensite transformations.