Processing of carbon containing gamma titanium aluminide alloys

Gamma-based titanium aluminide alloys have received much attention over the last decade with the intension of being used in turbine applications. In the as-cast state these alloys are relatively brittle when compared with conventional materials. In order to meet property requirements, optimisation of both alloy composition and microstructure are necessary. Alloys based on Ti-45Al-(5-10)Nb (at.%)with carbon additions seems capable of meeting many of the properties necessary for application. This paper addresses the reasons behind the choice of this alloy composition and discusses a relevant processing route.