The future use of gamma titanium aluminides by Rolls‐Royce

Gamma titanium aluminide is a material essential for meeting military and civil engine performance targets in the future and potentially it could be used throughout the engine from compressor to combustor to turbine. The current alloy being used within Rolls‐Royce is the established Ti‐45‐2‐2‐XD. This is competing for lower temperature applications such as stators and structural components which take advantage of the lower costs arising from the casting route. Rigorous design criteria are required to compensate for the risks in using these relatively new materials in components and this requires investigation into the effects of manufactured surface conditions, of microstructures local to load bearing regions and of compositional variations. For the future, Rolls‐Royce has patented a next generation gamma titanium resulting from alloy development programmes undertaken by the University of Birmingham. The aim is to optimise castability with strength and creep resistance and their potential for commercial use within the aero‐engine is discussed.