The present work proposes to investigate the mechanisms of the hot and the superplastic (SP) deformation behaviour for a two-phase Titanium alloy (Ti-6Al-4V) that presents an allotropic transformation between alpha (HCP) and beta (BCC) phases. In situ time of flight (TOF) neutron diffraction experiments performed during thermo-mechanical loadings under an argon atmosphere could allow to study the dynamic microstructural evolutions (phase fraction, lattice strain in each phase versus the stress, correlation with changes in chemical composition and local stresses..). The aim is then to follow in-situ the deformation mechanisms involved in each phase: alpha (HCP) and beta (BCC) and their respective contribution to the total strain for different conditions (temperature/strain rate).
