| Nowadays,magnet materials are widely used in production and life with their excellent performance.And with the development of science and technology,new requirements for the performance of magnet materials have also been put forward.The researchers found that Fe-Er-Cr and Fe-Si-Nb alloys prepared by adding Er,Cr and Si,Nb to Fe can not only greatly improve their magnetic properties,but also improve mechanical properties and mechanical properties through grain refinement.And it is ideal for future new magnet materials.The thermodynamic information of the phase diagram is the basis for the development of new materials.Therefore,in this paper,combined with the key research and development plan of the 13th Five-Year Plan of the Ministry of Science and Technology（2018YFE0306100）,the Fe-Er-Cr and Fe-Si-Nb ternary system phases are analyzed by experiments and calculations.The equilibrium relationship and thermodynamic information are systematically studied,and the main work is as follows:（1）The isothermal sections of Fe-Er-Cr ternary system at 1273 K,1073 K and 973 K were experimentally determined by the equilibrium alloy method combined with EPMA,XRD and SEM.Six three-phase regions and one ternary compound,Er Cr2Fe10,were found to exist at all three temperatures.Theσphase was found only at 973 K,and its phase equilibrium relationship was different from 1273 K and 1073 K.It is found that Er Fe2,Er Fe3,Er6Fe23and Er2Fe17can dissolve Cr in a certain range,and their solid solubility first decreases and then increases as the temperature decreases.At the same time,it is found that Er has a small amount of dissolution inα（Fe,Cr）.（2）The Fe-Si-Nb ternary system was thermodynamically optimized by the CALPHAD method,and a reasonable set of thermodynamic parameters was obtained.The isothermal sections of the Fe-Si-Nb ternary system at 1473 K,1373 K,1273 K,1173 K,and 1073 K was calculated,which were in good agreement with the latest experimental results. |
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