Microstructure and chemical composition of phases in Ti-48Al-2Cr-2Nb intermetallic alloy

The microstructure of the alloy and chemical composition of phases in as-cast and heat-treated conditions were characterized by scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX) spectroscopy. It has been shown that at high heating and cooling rates the thickness of the α2 and γ lamellae decreases. Also, under these conditions the surface area of the grain boundaries decreases. Higher annealing temperatures in the two-phase (γ+α) range and low cooling rates led to a lamellar microstructure. Annealing near the eutectoid temperature resulted in degeneration of the initial lamellar microstructure