Phase equilibria in nickel rich Ni–Al–Mo and Ni–Al–W alloys

Abstract

AbstractPhase equilibria have been investigated in the Ni rich regions of the Ni–Al–Mo system at 1473 K and of the Ni–Al–W system at 1523 and 1273 K using electron microprobe analysis, X-ray diffraction, and optical metallography. The phase relationships at 1473 and 1523 K are similar in the two systems showing three-phase equilibria of γ + γ′ + α (Mo or W) and γ′ + β + α (Mo or W); no ternary compounds were found in the regions studied. The maximum solubilities of Mo and W in γ′ were found to be ∼6 at.-%. Differences between the present and previous work are reviewed.