Abstract：The Ti-Al-Nb ternary alloy samples were prepared by vacuum melting, and then annealed at 1 000, 900, and 800 ℃ for 720, 1 440, and 2 160 h in furnace, respectively. Finally, these samples were quickly quenched to retain the high temperature structure. The vertical section of 50Ti-xAl-yNb in Ti-Al-Nb system was studied using X-ray diffraction analysis (XRD), differential thermal analysis (DSC) and electron probe microanalysis (EPMA). This work focused on detecting the change of phase zone in the middle temperature region (800-1 000 ℃). Five three-phase equilibrium zones: σ+β+α2, σ+O+α2, α2+γ+β, α2+γ+σ and α2+σ+τ; two two-phase equilibrium regions: β+O and α2+γ; and two single-phase regions: γ and β have been measured.
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2020, Vol. 25 
