Thermodynamic assessment of the Ir–Zr system

The Ir–Zr system has been critically assessed by means of the CALPHAD technique. The solution phases (liquid, body-centered cubic, face-centered cubic and hexagonal close-packed) were modeled with the Redlich–Kister equation. The intermetallic compounds Ir3Zr, αIrZr and βIrZr, which have a homogeneity range, were treated as the formulae (Ir, Zr)3(Ir, Zr), (Ir, Zr)Zr and (Ir, Zr)(Ir, Zr) by a two-sublattice model with Ir and Zr on the first sublattice, Ir and Zr or Zr on the second one, respectively. The other intermetallic compounds were treated as stoichiometric compounds. A set of self-consistent thermodynamic parameters of the Ir–Zr system was obtained.