Фазовая диаграмма системы Mg-Sb

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Mg-Sb

Mg-Sb (Magnesium-Antimony) A.A. Nayeb-Hashemi and J.B. Clark The Mg-Sb phase diagram originally was determined by [06Gru] and revised by [ 34Gru] to incorporate the high-temperature allotropy of Mg3Sb2, the only compound in the system. The thermal analyses of [06Gru] and [34Gru] are the only independent thermal analysis investigations of the system. They reported no solid solubility of Sb in (Mg) or of Mg in (Sb) in spite of a favorable size factor (the atomic radius ratio of (Sb/Mg) is 1.09; thus, the atomic size difference is less than 15%). The assessed Mg-Sb phase diagram is based primarily on the results of [34Gru], with some adjustments based on the work of [41Jon], [62Bol], and [71Rao]. Using experimental emf versus temperature measurements of [71Rao] ( corresponding to the liquid and (liquid + solid) alloys of more than 40 at.% Sb), the present evaluators have extracted the liquidus temperatures for some alloys on the Sb-rich side of the Mg3Sb2 compound. The (Sb) liquidus temperatures of [34Gru] are in excellent agreement with the calculated values in the present evaluation. On the Mg-rich side of the Mg3Sb2 phase, the polymorphic change involves a metatectic reaction at 894 C. On the Sb-rich side of the phase, [34Gru] presented a horizontal line at 930 C to show the polymorphic phase change in Mg3Sb2. However, an inflection in the cooling curve for the Sb-rich liquidus at 930 C shows that a three-phase reaction is involved. 06Gru: G. Grube, Z. Anorg. Chem., 49, 87-91 (1906) in German. 34Gru: G. Grube and R. Bornhak, Z. Elektrochem., 40, 140-142 (1934) in German. 41Jon: W.R.D. Jones and L. Powell, J. Inst. Met., 67, 177-188 (1941). 62Bol: K.A. Bolshakov, N.A. Bulonkov, and M.S. Tsirlin, Zh. Neorg. Khim., 7, 2272 (1962); TR: Russ. J. Inorg. Chem., 7(9), 1176 (1962). 71Rao: Y.K. Rao and B.V. Patil, Metall. Trans., 2, 1829-1835 (1971). Published in Phase Diagrams of Binary Magnesium Alloys, 1988, and Bull. Alloy Phase Diagrams, 5(6), Dec 1984. Complete evaluation contains 2 figures, 8 tables, and 30 references. Special Points of the Mg-Sb System