Liquidus and solidus temperatures of Ni-solid solution in Ni-Al-X (X: Ti, Zr, and Hf) ternary systems

A systematic investigation has been tarried out to determine both the gamma liquidus and solidus surfaces above the Ni solid solution in the Ni-AI-X ternary phase diagrams successively by differential thermal analysis. Each of the group IV elements in the periodic table, Ti, Zr, and Hf, was chosen as the ternary additive X in the present study. As a basis, gamma liquidus and solidus temperatures in the Ni-Al binary system were reinvestigated and evaluated. The gamma solvus was also taken into account to determine a temperature range for a solid-solution treatment above the gamma solvus, generally called "the window;" as well as the maximum solubility limit of gamma Ni solid solution.