Thermodynamic calculation of the Nd-Fe-B ternary system

来源 :第十七届全国相图学术会议暨相图与材料设计国际研讨会 | 被引量 : 0次 | 上传用户:laofei
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  Permanent magnets, especially for Nd2Fe14B-based sintered magnets, are used for various applications,e.g.magnetic resonance imaging devices, voice coil motors for hard disk drives and motors for hybrid/electric vehicles [1-3].The Nd2Fe14B based permanent magnets with good high performance were discovered and prepared on the basis of the phase relations of the Nd-Fe-B ternary system [4].Single Nd2Fe14B phase with α-Fe phase can only be obtained through strip casting [5].However, the Nd-Fe-B ternary phase diagram are still imperfection [6].In this work, thermodynamic databases of the three sub-binary systems in the Nd-Fe-B ternary system were critical reviewed based on the latest experimental thermochemical data [6].Then Nd-Fe-B ternary system based on these sub-binary systems and the reported experimental phase equilibria data and thermodynamic data were thermodynamically re-assessed using the generalized CALPHAD method.The self-consistent thermodynamic parameters obtained finally to describe the Gibbs energies of various phases in the Nd-Fe-B ternary systems can be used to reproduce well the reported phase equilibria and thermodynamic data.
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