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Microstructural evolution has been investigated in Si containing ? - Ti Al alloys after hot deformation and further annealing. Effective factors in thermomechanical processing such as deformation temperature, deformation ratio, and annealing temperature were studied. Isothermal deformation below the eutectic temperature resulted in inhomogeneous dynamic recrystallisation and fine equiaxed grains were produced in recrystallised areas and residual deformed lamellae elsewhere. During the deformation. the hard eutectic silicides play an important role in destruction of the as cast structure. Also the presence of the eutectic silicides and fine silicides produced by precipitation in the solid state restricts the size of grains produced by dynamic recrystallisation as well as by static recrystallisation on subsequent annealing and results in a fine grained structure.