Abstract:Samples of Ti26 (Ti-V-Sn-Cr-Al-Zr-Nb) alloy were compressed on the Gleeble−1500 heat stimulation machine. The compression test was carried out at 900−1 150 ℃ and strain rates from 0.001 s⁻¹ to 10 s⁻¹. Flow stress data at various temperatures and strain rate were obtained; and the compressive true stress vs. true strain curves were measured and studied. The deformation activation energy was calculated. The results show that the flow stress of Ti26 alloy decreases with the increase of temperature and the decrease of strain rate, and the deformation activation energy is 278.11 kJ/mol in b phase region. The flow stress curves and deformation activation energy reveal that the main softening mechanism is dynamic recovery in b phase region. Constitutive equations were formulated to describe the temperature dependence of the flow stress over a wide range of strain rates.

Key words: Ti26 titanium alloy; hot deformation; activation energy