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利用CALPHAD方法,选择和建立合理的热力学模型,并结合相平衡及热力学性质的相关信息,对Mo-RE (RE: Ce,Pr,Nd,Sm,Eu,Tb,Ho,Er, Tm,Yb,Lu)各二元系相图进行了热力学优化与计算.其中,液相和端际固溶体相的Gibbs自由能采用亚正规溶体模型描述,气相的Gibbs自由能采用理想气体模型描述.计算结果与实验数据取得了良好的一致性,最终得到了一组自洽的合理描述Mo-RE二元系各相自由能的热力学参数,建立了Mo-RE二元合金相图的热力学数据库.该热力学数据库可以提供相平衡及热力学性质等多种信息,为外推计算三元以及更多组元体系的相平衡提供理论基础,并为相关体系的合金设计及制备提供重要的理论指导.“,”Thermodynamic database of the Mo-RE (RE: Ce,Pr,Nd,Sm,Eu,Tb,Ho,Er,Tm,Yb,Lu) system was developed for the design of the Molybdenum-based refractory alloys.The thermodynamic calculation and optimization of Mo-RE binary system were performed using the calculation of phase diagrams (CALPHAD) method on the basis of experimental data including phase equilibrium and thermodynamic properties.The Gibbs energy of the liquid and solid solution phases was described by the sub-regular solution model,whereas that of the gas phases was described by the ideal gas model.The results show that a set of self-consistent thermodynamic parameters are obtained that reasonably describe the thermodynamic properties of the Mo-RE binary systems.A good agreement between calculated results and experimental data is achieved.The utility of this database is demonstrated in the thermodynamic calculation examples of the mixing enthalpy of liquid phase in the Mo-Ce and Mo-Pr system.Also,the 1200,1300,1400 ℃ isothermal section diagrams of the Mo-Ho-Tb system and related property diagrams like phase fraction of desired phases are depicted.Meanwhile,the Mo-Cu-Er ternary phase equilibrium section from 800 ℃ to 1000 ℃ is extrapolated.The results show fairly good prediction and provide much-needed information for the alloy design of the molybdenum-based refractory materials.