Investigation of the influence of Fe on the microstructure and properties of Ti5553 near-β titanium alloy with combinatorial approach

Abstract A combinatorial approach has been applied to build the database of composition dependent microstructure and hardness of the Ti5553–Fe system. The relationship between the composition and microstructure as well as the hardness was obtained. (Ti5553) 96 -Fe 4 was found to have almost the same hardness as that of Ti5553, but a relatively coarser intragranular α phase. High-angle annular dark field imaging revealed that Fe mainly concentrated in the β phase, which strengthened the β phase through solution strengthening. This means that (Ti5553) 96 -Fe 4 may have the same strength as that of Ti5553 but higher fracture toughness. The formation of FeCr compound consumed the β stabilizer elements Fe and Cr, which led to unusual increasing of the nucleation rate and the volume fraction of α phase in (Ti5553) 88 -Fe 12 .