Фазовая диаграмма системы Er-Ni

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Er-Ni (Erbium-Nickel) Y.Y. Pan and P. Nash The assessed Er-Ni phase diagram is based primarily on the work of [68Bus]. ErNi5 was observed to have a small homogeneity region on the Ni-rich side at high temperature. For the other phases, no solid solubility of either metal in the adjacent compound was indicated. ErNi and ErNi5 melt congruently at 1100 and 1380 C, respectively. Er3Ni, Er3Ni2, ErNi3, and Er2Ni17 were found to decompose peritectically at 845, 800, 1255, 1320, and 1315 C, respectively. Er2Ni7 is formed at 1275 C by the peritectoid reaction ErNi3 + ErNi4 = Er2Ni7. [68Bus] investigated the region near 80 at.% Ni and indicated that three more compounds exist between Er2Ni7 and ErNi5. The compositions were given as ErNi4, Er4Ni17, and Er5Ni22. The peritectic melting temperatures of these three phases occur close together, which makes it difficult to detect the thermal arrests, and the temperatures were not determined. The lattice parameter of (Er) measured by [68Bus] showed that the solubility of Ni in (Er) is negligible. No homogeneity region of (Ni) was observed. [68Bus] found that the alloy with approximately 38 at.% Ni became single phase when annealed at 700 C for 3 weeks, from which he concluded that a compound exists at this composition; its formula was assigned as Er5Ni3. [74Mor] reinvestigated this phase using single crystals with nominal stoichiometries ranging from Er1.5Ni to Er1.8Ni. Their single-crystal structure determination for these alloys suggested that the composition of this intermediate phase should be Er3Ni2 instead of Er5Ni3, and this is accepted in this evaluation. By quenching annealed samples from various temperatures, [68Bus] observed Er2Ni7 with the rhombohedral Gd2Co7 structure. However, this structure was absent if the sample were cooled too quickly from the melt, as it formed sluggishly. The lattice param-eters of this phase were measured on a single- phase sample of 77.8 at.% Ni, that was annealed for 26 days at 1000 C. [69Vir] reported two modifications at this composition, based on the examination of an alloy Er22.2Ni77.8. The Ce2Ni7-type phase is the low-temperature modification of Er2Ni7, probably stable up to 1200 C, and the high- temperature modification is Gd2Co7-type. The phase transformation at the composition Er2Ni7 is still uncertain, so it is regarded as a single phase in this evaluation. The variation of magnetization with temperature was measured by [64Abr] and the magnetic properties of the Er-Ni compounds were investigated systematically by [68Bus]. The results generally indicate rather low magnetic ordering temperatures. 59Wer: J.H. Wernick and S. Geller, Acta Crystallogr., 12, 662-665 (1959). 60Wer: J.H. Wernick and S. Geller, Trans. AIME, 218, 866-868 (1960). 64Abr: S.C. Abrahams, J.L. Bernstein, R.C. Sherwood, J.H. Wernick, and H.J. Williams, J. Phys. Chem. Solids, 25, 1069-1080 (1964). 64Wal: R.E. Walline and W.E. Wallace, J. Chem. Phys., 41(6), 1587-1591 (1964). 65Dwi: A.E. Dwight, R.A. Conner, Jr., and J.W. Downey, Acta Crystallogr., 18, 835-838 (1965). 66Bus: K.H.J. Buschow, J. Less-Common Met., 11, 204-208 (1966). 67Lem: R. Lemaire and D. Paccard, Bull. Soc. Fr. Min. Cristallogr., 90, 311- 313 (1967) in French. 67Pac: D. Paccard and R. Pauthenet, C.R. Acad. Sci. Paris B, 264(15), 1056- 1059 (1967) in French. 68Bus: K.H.J. Buschow, J. Less-Common Met., 16, 45-53 (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). 71Tay: K.N.R. Taylor, Adv. Phys., 20(N87), 551 (1971). 73Gig: D. Gignoux, J. Rossat-Mingad, F. Tcheou, and D. Paccard, Proc. 10th Rare Earth Res. Conf., Vol. 2, C.J. Kevane and T. Moeller, Ed., NTIS, Springfield, VA, 596-604 (1973). 74Mor: J.M. Moreau, D. Paccard, and E. Parthe, Acta Crystallogr. B, 30, 2583- 2586 (1974). Published in Phase Diagrams of Binary Nickel Alloys, 1991. Complete evaluation contains 6 figures, 4 tables, and 30 references. 1