The study on phase diagram of magnetic materials and alloys under high magnetic fields for development of new functional materials

在高达45T的磁场中，对铁磁性材料MnBi300-773K的温度范围进行了差热分析。在45T的磁场作用下，分解温度Tt(MnBi-&GT；Mn1.08Bi液)从632K提高到714K，并得到了18T时的BiMn相图，与零磁场下的相图有很大的不同。我们还得到了18T以上强磁场下的Fe-C钢相图。用计算机相图耦合(CALPHAD)方法对强磁场下的BiMn二元相图进行了热力学计算。计算结果表明，在磁场作用下，Bi-Mn相图发生了显著的变化，这与本课题组的场热分析实验结果吻合较好。

Differential thermal analysis was carried out for ferromagnetic material MnBi in the temperature range 300-773K in magnetic fields up to 45 T. The decomposition temperature Tt (MnBi -> Mn1.08 Bi + liquid) increases from 632 K (at a zero field) to 714 K by applying a magnetic field of 45 T. In addition, the Bi-Mn phase diagram at 18 T was obtained, which quite different from that at a zero magnetic field. We also obtained the Fe-C steel phase diagram under high magnetic fields over 18 T. The thermodynamic calculations of the Bi-Mn binary phase diagram in high magnetic fields are carried out by the Computer Coupling of Phase Diagrams (CALPHAD) method. The calculated results show the significant change of the Bi-Mn phase diagram under magnetic fields, which were in good agreement with the experimental results of in-field thermal analysis performed by our research group.