High‐temperature solid‐state reaction between zirconium carbide and iridium: New insights into the phase formation.

The reaction between ZrC and iridium powders was studied in the temperature range of 1000–1600°C. The reaction was stated to start at a temperature as low as 1000°C. The only high‐melting intermetallic phase, ZrIr3, was obtained as a substitutional solid solution ZrIr3±δ. A new analytical approach to relating the composition to the lattice parameter of cubic binary substitutional ZrIr3±δ solid solutions was proposed. This approach is based on comparing the distribution by elemental composition and by lattice parameter in a range of ZrIr3±δ solid solutions. This made it possible to determine the lattice parameter of a stoichiometric ZrIr3 phase, a0 = 3.971(5) Å. [ABSTRACT FROM AUTHOR]