Thermodynamic Properties of Melts of the Ternary System Ag–Al–Yb

Abstract

Isoperibolic calorimetry is used to determine the enthalpies of mixing of liquid alloys of the Ag‒Al–Yb system along two radial sections with a constant ratio of atomic fractions of aluminum and silver: (1) xAg/xAl = 0.46/0.54 at 1271 ± 1 K and (2) xAg/xAl = 0.19/0.81 for 1454 ± 5 K up to xYb ∼ 0.2. It is found that melts of the studied system form with the release of a small amount of heat (ΔHmin = −29 kJ/mol), and the minimum ΔH accounts for the middle of the concentration triangle. Using the geometric and analytical Redlich–Kister models, calculations are made for ΔH triple system melts Ag–Al–Yb using similar data for double boundary subsystems.