Фазовая диаграмма системы Ni-Sm

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Ni-Sm (Nickel-Samarium) Y.Y. Pan and P. Nash The assessed Sm-Ni phase diagram is based primarily on the work of [83Pan]. Seven previously reported compounds were confirmed: Sm3Ni, SmNi, SmNi2, SmNi3, Sm2Ni7, SmNi5, and Sm2Ni17. A new compound was formed at about 80 at.% Ni, which corresponds to the composition SmNi4. [83Tak] reported a stable phase at 79.2 at.% Ni, which was designated Sm5Ni19; this is accepted in this evaluation. No solid solubility of either metal was found in any of the compounds [83Pan]. Because the heat effect of these transformations on the DTA curves observed by [83Pan] is rather small, the Sm-rich portion of the assessed diagram is still not determined exactly. [70Bus] studied a sample of Sm2Ni7 that was annealed for 4 weeks at 900 C. They observed that the hexagonal form is the main phase, with the rhombohedral form present in amounts of about 20%; they suggested that the hexagonal form is stable at high temperatures, and that the rhombohedral form is the low- temperature modification. [83Pan] came to the same conclusion. Because the temperature of transformation has not been determined, Sm2Ni7 is represented as a dashed line in the assessed diagram at low temperatures. [67Laf] reported the Curie temperature of compound Sm2Ni7 to be 186 K, but [ 68Car] claimed it should be 641 K. [73Wal] argued that the data of [68Car] are more precise, because of better control and assessment of impurities. 66Bus: K.H.J. Buschow, J. Less-Common Met., 11, 204-208 (1966). 67Laf: J. Laforest, R. Lemaire, D. Paccard, and R. Pauthenet, Compt. Rend. B, 264, 676-679 (1967) in French. 67Lem: R. Lemaire and D. Paccard, Bull. Soc. Fr. Min. Cristallogr., 90, 311- 315 (1967) in French. 68Car: P.D. Carfagna and W.E. Wallace, J. Appl. Phys., 39, 5259-5262 (1968). 68Man: R.C. Mansey, G.V. Raynor, and I.R. Harris, J. Less-Common Met., 14, 329- 336 (1968). 69Vir: A.V. Virkar and A. Raman, J. Less-Common Met., 18, 59-66 (1969). 70Bus: K.H.J. Buschow and A.S. Van Der Goot, J. Less-Common Met., 22(4), 419- 428 (1970). 73Wal: W.E. Wallace, Rare Earth Intermetallics, Academic Press, New York, 111- 144 (1973). 83Pan: Y.Y. Pan and C.S. Cheng, Acta Phys. Sin. (China), 32(1), 92-95 (1983) in Chinese. 83Tak: S. Takeda, H. Horikoshi, and Y. Komura, J. Microsc., 129(3), 347-358 ( 1983). Published in Phase Diagrams of Binary Nickel Alloys, 1991. Complete evaluation contains 2 figures, 4 tables, and 24 references. Special Points of the Sm-Ni System