Influence of heat treatment on the precipitation of γ1 phase in high Nb containing TiAl-based intermetallic alloys

Abstract A new intermetallic compound γ1 (Ti4Nb3Al9) phase can be observed with the increasment of Nb content in the Ti-Al-Nb ternary system. This work deals with the influence of heat treatment on the precipitation of γ1 phase in high Nb containing TiAl-based intermetallic alloys. The experiment results showed that 1400°C was acceptable as the homogenization temperature for the super-high Nb containing TiAl-based alloys. The new γ1 phase precipitated from the γ phase matrix during the following furnace cooling process. TEM and XRD tests were applied to identify γ1 phase. The experimental results revealed that γ1 phase could precipitate from the Ti-48Al-10Nb alloy after exposure at 1200°C for 100-240h.