Thermodynamic assessment of the terbium–gold binary system

• Rare earth elements are increasingly used in advanced materials (permanent magnets, hydrogen storage alloys, luminescent materials …).
• To our knowledge, this system was not previously optimized.
• The present work gives a new set of thermodynamic quantities which are inaccessible to the experimental measurements especially as literature put forwards the experimental difficulties encountered by several coworkers.
• The reliability of our calculated parameters was checked applying extra criterion to test their stability especially at high temperatures.

The Tb–Au system was critically assessed by means of the CALPHAD technique. The liquid and the solid solution phases, fcc_A1, bcc_A2 and hcp_A3, were treated with the substitutional solution model. The binary intermetallic compounds were treated as stoichiometric phases. All the thermodynamic parameters of various phases have been optimized and the calculated results are in reasonable agreement with experimental data.