Cold-Rolling Technology of Wrought High-Nb Dual Phase TiAl Alloy and Its Microstructure as well as Mechanical Properties

Abstract:

High-Nb dual phase wrought TiAl alloys were cold-rolled under accurate control by small-pass reduction process. Results show that the deformation of the whole sample is uniform after cold rolling, and the maximum total deformation amount would be more than 20% in the case of no intermediate annealing. The microstructure of the deformed alloy still kept a dual phase structure; γ grains were elongated along rolling direction; the residual lamellar changed from the initial disordered distribution to the distribution of keeping a definite angle to rolling direction. The annealing tests reveal that different reductions, annealing temperatures and annealing time have obvious effect on the mechanical properties and structure of the cold rolled high-Nb TiAl alloy; therefore the intermediate annealing process corresponding to different reductions are also different.