Abstract：Phase equilibria of the Nd-B-Sm system were investigated through a combination of experiments and calculations of phase diagram. Based on the sub-binary phase diagrams, seven ternary alloys with different composition were designed and prepared using an electric arc melting furnace. Phase constituents of the Nd-B-Sm alloys annealed at 773 K, 873 K and in the as-cast state were investigated using electron probe microanalysis and X-ray powder diffraction. The results indicate that due to the similarity in atomic radii and electronegativity between Nd and Sm, the Nd-B and Sm-B compounds share identical crystal structures so that Nd₂B₅ and Sm₂B₅ form an infinite solid solution of (Nd,Sm)₂B₅, with no ternary compounds observed. Base on the phase equilibrium data obtained in this work and thermodynamic description on the binary systems reported in the literature, a set of self-consistent thermodynamic parameters is obtained by thermodynamic optimization of the Nd-B-Sm system using the CALPHAD method. The calculated isothermal sections at 773 K and 873 K, the liquidus projection, and the Scheil solidification path are in good agreement with the experimental data.
梅家成, 仇成亮, 刘树红, 杜勇. Nd-B-Sm体系的相图热力学研究[J]. 粉末冶金材料科学与工程, 2025, 30(4): 289-300.
MEI Jiacheng, QIU Chengliang, LIU Shuhong, DU Yong. Phase diagram thermodynamic investigation of the Nd-B-Sm system. Materials Science and Engineering of Powder Metallurgy, 2025, 30(4): 289-300.
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