The Effect of Ti Addition on Phase Equilibria among Ni (A1), Ni3Al (L12) and Ni3V (D022) Phases
The effect of Ti addition on phase equilibria among Ni (A1), Ni3Al (L12) and Ni3V (D022) phases at 950 °C was investigated through TEM/EDS analysis on heat-treated alloys. The three-phase coexisting region of A1 + L12 + D022 was found to exist around the composition of Ni-4Al-19V (at. %) in the Ni-Al-V ternary system. With addition of Ti to the ternary system the three-phase coexisting region was shifted to the Ni-rich side. Ti partitioned most into the L12 phase and least into the A1 phase. These results suggest that the addition of Ti stabilizes the L12 and D022 phases against A1 phase, and raises the temperature of eutectoid reaction in the Ni3Al-Ni3V pseudo-binary system: A1 → L12 + D022.
Jian-Feng Nie and Allan Morton
E. Hayashi et al., "The Effect of Ti Addition on Phase Equilibria among Ni (A1), Ni3Al (L12) and Ni3V (D022) Phases", Materials Science Forum, Vols. 654-656, pp. 432-435, 2010