Neutron diffraction study of texture development during hot working of different gamma-titanium aluminide alloys

The evolution of preferred orientations during processing appears to be of significant importance for the use of γ-titanium aluminide alloys, since the desired lamellar microstructures exhibit a strong anisotropy of mechanical properties. In this work, texture development has been investigated after hot extrusion and sheet rolling, which are considered to be technologically relevant wrought processes. As texture evolution certainly is dependent on several factors, involving deformation properties, recrystallization kinetics, and, particularly, the phase constitution at hot-working temperature, different processing conditions and alloy compositions were investigated. By comparing the results, it is indicated that the determined textures can be understood by the deformation modes of the dominating phase at hot-working temperature and the subsequent phase transformations. However, the current understanding of texture evolution is far from being complete, as no model can be presented which quantitatively accounts for the contribution of the different processes mentioned.