Hot deformation characteristics and microstructural evolution of Ti-900 alloy

Hot deformation behaviour of Ti -900 (Ti-6.5Al-3.2Mo-1.8Zr-0.25Si) alloy has been analyzed by conducting an isothermal hot compression test at 850 C-degrees to 1050 C-degrees temperatures and strain rates between 0.001 s(-1) to 10 s(-1). The effect of strain rates and deformation temperature on flow stress is investigated. The processing maps are constructed, and constitutive equations are studied to understand the formability of the novel titanium alloy in the different temperatures and strain rates regimes. Results suggest that temperatures and strain rates between 880 C-degrees to 950 C-degrees and 0.001 s(-1) to 0.01 s(-1) are the optimal processing window for this alloy. The kinetic rate equation indicates that the apparent activation energy for deformation is 531 kJ/mol in the alpha + beta region. Post deformation microstructure formation is also studied.