Tensile creep tests were conducted on directionally solidified TiAl alloys
to discern the effect of alloying and lamellar orientation. A seeding techn
ique was used to align the TiAl/Ti3Al lamellar structure parallel to the gr
owth direction for alloys of Ti-47Al, Ti-46Al-0.5Si-0.5X (X = Re, W, Mo. an
d Cr), and Ti-46Al-1.5Mo-0.2C (at.%). Tensile creep tests were performed at
750 degreesC using applied stresses of 210 and 240 MPa. Aligning the lamel
lar microstructure greatly enhances the creep resistance which can further
be improved by additional alloying. (C) 2001 Elsevier Science Ltd. All righ
ts reserved.