Critical thermodynamic evaluation and optimization of the Fe–B, Fe–Nd, B–Nd and Nd–Fe–B systems

All experimental data on phase equilibria and thermodynamic properties of the Fe–B, Fe–Nd and Nd–B binary and Fe–Nd–B ternary systems in literature were reviewed and critically examined. A set of optimized model parameters for all solid stoichiometric compounds, solid solutions and liquid phase was built to reproduce all available reliable thermodynamic properties and phase diagram data within experimental error limits. The solid solutions were modeled using the Compound Energy Formalism. The Modified Quasichemical Model in the pair approximation was used to describe the thermodynamic properties of the liquid solution accurately. The database of the model parameters can be used, along with the software for Gibbs energy minimization, to calculate any type of phase diagram section. Unexplored liquidus projection of the Fe–Nd–B ternary system was predicted from the thermodynamic models and optimized parameters.

► Complete critical evaluation of all available phase diagram and thermodynamic data for the Fe–Nd–B system for the first time.
► Thermodynamic database of optimized model parameters has been developed.
► Gibbs energies of binary and ternary solid and liquid phases were properly described.
► All reliable thermodynamic and phase diagram data were properly reproduced.
► Liquidus projection of the Fe–Nd–B system is properly predicted for the first time.