Abstract
Intermetallic titanium aluminides exhibit attractive thermophysical properties, which give them the potential for extensive use as lightweight structural components. Novel design concepts are based on alloys with the general composition (in at.%) Ti-45Al-(5-10) Nb, which were subjected to precipitation hardening. Optimized compositions have been identified that are capable of carrying stresses in excess of 700 MPa at service temperatures of 700 degrees C and have superior creep properties. The alloys exhibit at room temperature yield stresses in excess of 1GPa combined with plastic tensile elongations of about 2%. Wrought alloys of this type can be an attractive alternative to the nickel-base superalloys in certain ranges of stress and temperature. The future and promise of these new TiAl alloys lies in innovative processing methods designed to achieve better performance.
DOI Link to Publication