Microstructure and mechanical properties of high niobium containing TiAl alloys elaborated by spark plasma sintering

Depending on the sintering temperature, two-phased, duplex and lamellar microstructures have been obtained. A quasi-α2 phase has been observed, which is in fact an α2 phase in which Nb atoms have substituted Ti atoms. The TNB alloys consolidated by SPS are stronger than the alloys previously elaborated by SPS using Ti-47Al-2Cr-2Nb and Ti-44Al-2Cr-2Nb-1B powders but they exhibit a lower ductility. Moreover, some specimens broke prematurely due to Fe inclusions.