During annealing on the Ti surface coated by the Al film, different aluminide phases were formed as the result of reactions between Ti and Al. Preliminary irradiation of the Al film with the thickness of 7μm by Ti+ ions had a strong effect on the interdiffusion growth of aluminide phases on the Ti substrate. Preliminary ion irradiation resulted in the development of more homogeneous and fine-grain microstructure during subsequent annealing. During ion irradiation of the two-phase (TiAl+Ti3Al) overlayer the decomposition of the TiAl compound and the formation of Ti3Al happened. In the processing of subsequent annealing, diffusion cementation of the overlayer occurred faster on the surface of the irradiated samples. After irradiation by different ions (Ti+ and Al+), and during subsequent annealing the kinetics of structural formation developed in a different way.

Effect of Ion Irradiation on the Interdiffusion Growth of Aluminide Phases in Ti–Al Diffusion Couple. S.E.Romankov, A.Mamaeva, E.Vdovichenko, E.Ermakov: Nuclear Instruments and Methods in Physics Research Section B, 2005, 237[3-4], 575-84

Figure 9

Interdiffusion in Ti/TiAl