Characterization of titanium aluminide alloy components fabricated by additive manufacturing using electron beam melting

Intermetallic, γ-TiAl, equiaxed, small-grain (∼2 μm) structures with lamellar γ/α2-Ti3Al colonies with average spacing of 0.6 μm have been fabricated by additive manufacturing using electron beam melting (EBM) of precursor, atomized powder. The residual microindentation (Vickers) hardness (HV) averaged 4.1 GPa, corresponding to a nominal yield strength of ∼1.4 GPa (∼HV/3), and a specific yield strength of 0.37 GPa cm3 g−1 (for a density of 3.76 g cm−3), in contrast to 0.27 GPa cm3 g−1 for EBM-fabricated Ti–6Al–4V components. These results demonstrate the potential to fabricate near net shape and complex titanium aluminide products directly using EBM technology in important aerospace and automotive applications.