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Thermodynamic assessment of the Fe-Nd-B phase diagram

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Journal of Phase Equilibria

Abstract

A thermodynamic description of all stable phases of the Fe-Nd-B system is presented. This description was obtained by the optimization of experimental thermochemical and phase diagram data from literature using a least-square method. Previous assessments of the three limiting binary systems were incorporated. A reassessment of the Nd-B phase diagram is performed, taking into account the experimental information of the ternary system. The calculated results are in excellent agreement with the experimental data. A reaction scheme is presented, accounting for all invariant reactions in the system. This leads to some differences with earlier suggestions regarding the phase relations in composition regions where the amount of experimental data is limited. It is expected that the present description could therefore provide an answer to some of the remaining conflicts between phases one would expect from the previously suggested phase diagrams and what is actually observed.

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Hallemans, B., Wollants, P. & Roos, J.R. Thermodynamic assessment of the Fe-Nd-B phase diagram. JPE 16, 137–149 (1995). https://doi.org/10.1007/BF02664851

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