Titanium Aluminide Applications in the High Speed Civil Transport

SummaryMany of the presented advancements in casting, fabricationand joining technologies tor TiAI are attributed to the HSRprogram. Much more work is required to achieveacceptance of this material system within the designcommunity. However, the potential weight savings of TiAIover conventional superalloys have enticed designcnginecrs to consider this matcrial for high temperatureapplications where high stiffness is required. Eachsuccessful accomplishment in programs such as RLV andHSR creates an optimistic future for TiAI in aerospaceapplications. To truly capitalize on the potential for thisclass of material, more research is required. Areas forimprovement include low cost material production, robust,joining methods, and increased materials propcrtydatabase.AknowledgcmentsThe authors would like to acknowledge the dedicatedresearchers of the HSR exhaust nozzle program lot theircontributions towards thc advancement of TiAI materialsystems for aerospace applications. Without thecontributions of the following people this work would nothave advanced this far: Srivats Ram of Precision CastpartsCorporation: Thomas Kelly and Russell Smashey ofGcneral Electric Aircraft Engines: Gopal Das,Robert Warburton, and Steve McLeod of Pratt & Whitney;and Helmut Clemens of Piansee.RefcrencesI R.J. Shaw, L. Koops, and R. Hines, "Progress TowardMeeting the Propulsion Technology Challenges for a 21 stCentury High-Speed Civil Transport", (NASA TM 113161/ISABE 97-7045), 1997.Nishiyama, Y., Miyashita, T., lsobe, S., and Noda, T.,Proceedings of 1989 Symposium on High TemperatureAluminides and lntermetallics, 1989, pp557-573.Larsen, D.E., Wheeler, D.A., and London, B., "Processingand Manufacture of Gamma and XD