Фазовая диаграмма системы Be-Sb

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Be-Sb

Be-Sb (Beryllium-Antimony) H. Okamoto and L.E. Tanner A tentative Be-Sb equilibrium diagram has been constructed on the basis of a number of separate and diverse experimental observations. There appear to be at least four intermediate phases in this system, although some may be either metastable or stable in rather limited temperature ranges. [64Uga] made a compound of nominal stoichiometry Be3Sb2 by vapor deposition on a substrate at 450 to 480 C. However, this phase did not form when the substrate temperature was lowered to below 400 C; below this temperature Be and Sb were deposited separately. A cubic phase, Be2Sb3, formed at 1075 C under 35 bar and was retained at ambient pressure [71Sto]. The BeSb2 compound was prepared by solid- state reaction between elements in sealed tubes at 700 C [76Ger]. According to [77Haa], Be13Sb and two other fcc phases were produced when a molten mixture of composition 2Be + 1Sb was cooled from 1280 to 600 C over a period of 4 h, and then to room temperature over the next 14 h. One of these fcc phases may correspond to BeSb2, because the respective lattice parameters are similar. The prior observations can be summarized with reasonable consistency in the tentative assessed phase diagram, although further studies are necessary to establish a systematic confirmation of these various observations. The melting point of bBe and the bBe = aBe allotropic transformation temperature are 1289 с 5 and 1270 с 6 C, respectively [Melt]. The melting point of aSb is 630.775 C [Melt]. The melting points of the intermediate phases are not known, and there are no reports on solubility ranges. 64Uga: Ya.A. Ugai, V.L. Gordin, and V.Z. Anokhin, Zh. Neorg. Khim., 9(1), 218- 220 (1964) in Russian; TR: Russ. J. Inorg. Chem., 9(1), 119-120 (1964). 71Sto: A.J. Stonehouse, US Patent No. 3574608; Chem. Abstr., 74, P145675m ( 1971). 76Ger: R. Gerardin and J. Aubry, J. Solid State Chem., 19, 239-244 (1976) in French. 77Haa: A. Haase and M. Martinez-Ripoll, Acta Crystallogr. B, 33, 555-557 (1977) . Published in Phase Diagrams of Binary Beryllium Alloys, 1987. Complete evaluation contains 1 figure, 1 table, and 6 references. 1