Phase transformations in γ based titanium aluminides

Abstract

There have been many recent advances in the development of γ based titanium aluminides for high temperature load bearing applications. Several improvements in the properties of these materials have been the direct result of better understanding of the phase transformations and microstructural evolution in this system. Engineering applications focus on the use of the lamellar microstructure, consisting of alternating plates of the γ and α₂ phases. The solidification microstructures, phase transformations in the relevant phase fields, interfacial structure, thermomechanical treatments, and alloying effects are surveyed. Some areas of current interest and unresolved issues are highlighted.