Hot Workability of Orthorhombic Ti-22Al-11Nb-2Mo-1Fe Alloy

摘要

The hot workability of orthorhombic Ti2AlNb-based Ti-22Al-llNb-2Mo-lFe alloy has been investigated by hot compression tests in the temperatures from 800 to 1100°C with the strain rates of 0. 01 to 10 s-1. The effect of the starting microstructure on flow deformation showed that the higher flow stresses are obtained for the lamellar microstructure as compared to those for the equiaxed microstructure. The shear banding flow-localization-controlled failure and fracture during sub-transus hot compression have been found in lamellar or equiaxed microstructure of this alloy. The influences of hot compression variables on flow behaviors are discussed. The hot workability map of Ti-22Al-llNb-2Mo-lFe alloy has been investigated. The uniform deformation can be obtained in all of strain rate above 1000°C and the lower strain rates at 950°C.