γ-TiAl based alloys are currently of great interest as potential replacements for nickel-based superalloys for different application fields such as turbine blades for aircraft engines, stationary turbines and space vehicles because of their light weight, high strength and good creep characteristics. The two current basic routes of manufacturing are near net-shape casting and extrusion coupled to forging. In this work we consider a more recent freeform fabrication technique: electron beam melting (EBM), in which an electron beam is used to realize a selective densification of metal powder by melting it in a layerwise manner following a CAD design. In particular the relation between powder characteristics such as granulometric distribution, chemical composition, flowability etc on the EBM process has been investigated. The resulting microstructure was analysed, with particular attention to residual porosity of the final component.
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