The incoherent γ/γ′ solvus in Ni-Al alloys


Analysis of the kinetics of solute (Al) depletion during the coarsening of γ′ (Ni 3 Al)precipitates has been used in earlier investigations to provide values of the coherent solubility of the γ phase in binary Ni-Al alloys. As demonstrated in recent experimental investigations, the coherent solubility is a function of the total concentration of Al in the two-phase alloy. Using the model of Ardell and Maheshwari to analyze the data on coherent equilibrium, the authors estimated the incoherent equilibrium solubility of the γ′ phase over the temperature range 400 to 800 ° C. The calculated incoherent solubility limits are 3 to 5 % smaller than previously published measurements, the differences decreasing as the temperature increases. The authors argue that the calculations in this article provide the first estimates of the incoherent solvus of the γ′ phase in Ni-Al alloys.

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Li, F., Ardell, A.J. The incoherent γ/γ′ solvus in Ni-Al alloys. JPE 19, 334 (1998).

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  • Lattice Misfit
  • Recent Experimental Investigation
  • Coherent Equilibrium
  • Coherent Solvus