The alloy design and efficient routes of TiAl processing are important technological challenges. Gamma-TiAl alloys are potential replacements for nickel and conventional titanium alloys in hot sections of turbine engines, as well as in sub-structures of orbital platform vehicles. Powder metallurgy is a near net shape process that allows the parts production with complex geometry at low costs. In this work, samples of Ti-48AI-2Cr-2Nb (at.%) were prepared from elemental and pre-alloyed powders mixed for 2 h, followed by cold uniaxial and isostatic pressing using three specific routes with sintering and hot pressing stages between 1100 up to 1400°C, for 1 h. After metallographic preparation, sintered samples were characterized by SEM (Scanning Electron Microscopy) and density analyses. The results indicate that a full lamellar microstructure is obtained by the pressureless routes while a duplex microstructure is present in samples produced by hot pressing route.
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