Role of microstructure on the tension/compression asymmetry in a two-phase Ti-5Al-3Mo-1.5V titanium alloy

An investigation was conducted to understand the role of microstructure on the asymmetry of mechanical properties in quasi-static tension and compression in a two-phase titanium alloy Ti-5Al-3Mo-1.5V. Different microstructures were obtained (lamellar colony, basketweave and martensitic) on adopting different cooling rates after solution treatment in single phase beta region. The microstructure with martensite exhibited higher strain to failure and lower yield strength than basketweave. Detailed TEM microstructural analysis helped reveal the existence of compression twins and strain-induced phase transformation in compression and tension tests respectively, both of which are relatively rare to be observed in two-phase titanium alloys. (C) 2019 Elsevier B.V. All rights reserved.