Evolution of the microstructure during hot working of gamma-based TiAl alloys

Cast products of two-phase titanium aluminides suffer from microsegregation of the alloying elements, which arises from the peritectic solidification pathway. The resulting variation in composition and microstructure occurs o n a length scale in the range of I min and, thus, cannot be tolerated for t he anticipated applications of the materials. A significant structural and chemical consolidation can be achieved by homogenization and hot-working pr ocedures, however, the processing experience is limited. This problem is ad dressed in the present paper in that the evolution of the microstructure of two-phase alloys after different stages of wrought processing is character ized by structural and chemical microanalysis involving scanning electron m icroscopy and energy dispersive X-ray analysis. The investigations involve different two-phase alloys in order to assess the effects of ternary and hi gher alloying elements on the finally obtained microstructure.