COST-EFFECTIVE PRODUCTION OF POWDER METALLURGY

TiAl-BASED COMPONENTS FOR AEROSPACE USE

 
Gamma titanium aluminide (TiAl) alloys with their low density (~3.9 g/cm3), good elevated temperature strength, stiffness, creep resistance and acceptable burn and oxidation resistance have excellent potential for use in high temperature aerospace applications at temperatures between 500°C to 1000°C instead of the currently used high density (~8.9 g/cm2) Ni-based superalloys. However, its poor intermediate and room temperature ductility cause conventional manufacturing operations such as rolling, forging, or drawing to be difficult for titanium aluminides, thus leading to very high cost of TiAl components, both sheet and foil (currently this is costing up to $10,000 per 30” by 12” by 0.04” sheet) and “chunky” parts. Thus in the program cost-effective flat products (sheets/foils) and NNS “chunky” components of monolithic TiAl is fabricated by a patented loose sintering approach. These components can be used in next generation launch vehicle airframe (experiencing extensive aerodynamic heating) and engine applications.
 

 

 

 

 

 

 

 

 

                                                    Cross-section microstructures of TiAl sheet  with a thickness of 0.029-inch