Growth kinetics of TiAl3 layer in multi-laminated Ti–(TiB2/Al) composite sheets during annealing treatment

The growth of TiAl3 is a critical stage during the fabrication of TiAl sheets employing Ti and Al sheets. In the present work, Al sheets were replaced by TiB2/Al composites for (i) the production of TiB2–TiAl composite sheets and (ii) a better deformation compatibility. The formation mechanism and growth kinetics of TiAl3 layer in the multi-laminated Ti–(TiB2/Al) composites were systematically investigated between 600 °C and 650 °C. The formation of TiAl3 was a reaction–diffusion process accompanied by its order–disorder transition, its growth towards TiB2/Al layers was found faster than that towards Ti layers. The introduction of TiB2 particles had little influence on the growth of TiAl3 layer which followed the parabolic growth law. The activation energy for growth of TiAl3 layer was estimated to be 254.9 kJ mol−1.