Recent progress in experimental and theoretical studies of the diffusion behavior of this system was reviewed. Modern experimental methods were briefly described, and recent experimental results for Ti and Al diffusion in α-Ti(Al), β-Ti(Al) and the intermetallic phases, α2-Ti3Al and γ-TiAl, were summarized. Results on interdiffusion and impurity diffusion in these phases were discussed in detail. A summary was also given of the current understanding of point defects and diffusion mechanisms in Ti3Al and TiAl. A statistical model was presented for point-defect disorder in ordered compounds, and was applied to Ti3Al and TiAl by using input data which were generated by embedded-atom potentials. The possible atomic diffusion mechanisms in these compounds were analyzed in detail, and methods for diffusional calculations involving various mechanisms were reviewed. The relative importance of various mechanisms in Ti3Al and TiAl was evaluated by comparing their estimated activation energies.

Diffusion in the Ti-Al System. Y.Mishin, C.Herzig: Acta Materialia, 2000, 48[3], 589-623