Micro-mechanical modelling of the deformation behavior of γ-TiAl-based alloys was based on a strong correlation between numerical simulations and experimental investigations. Most attention was devoted to a near-γ microstructure which contained equiaxed γ-grains and α2-phase located at grain boundaries and triple junctions. An investigation was made of the deformation mechanisms of polycrystalline near-γ material by using both computational finite element simulations and acoustic emission measurements. A 3-dimensional micro-mechanical model, which had originally been developed in order to describe lamellar γ-TiAl, was adjusted so as to simulate the deformation behavior of polycrystalline near-γ material. The contribution of deformation twinning to the total plastic deformation was deduced for compression tests at room temperature. The onset of twinning was related to experimental data obtained from acoustic emission measurements.

On the Role of Twinning during Room-Temperature Deformation of γ-TiAl Based Alloys. W.T.Marketz, F.D.Fischer, F.Kauffmann, G.Dehm, T.Bidlingmaier, A.Wanner, H.Clemens: Materials Science and Engineering A, 2002, 329-331, 177-83