Фазовая диаграмма системы Sb-Ti

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Sb-Ti (Antimony-Titanium) J.L. Murray Based on sparse microstructural data, [Hansen] composed a schematic phase diagram showing equilibrium compounds Ti4Sb, TiSb, and TiSb2. The diagram was intended to convey that (1) TiSb and Ti4Sb melt congruently and consequently at least two eutectic reactions occur on the Ti-side of TiSb [51Now]; (2) the solubility of Ti in (Sb) is sufficiently low that the lattice parameter of Sb is not affected [51Now]; and (3) TiSb2 forms peritectically from the melt. Specifically, the reaction L + TiSb = TiSb2 occurs at 1010 C, and the liquidus temperature is 1030 C at 33.3 at.% Sb ([60Dud], thermal analysis). The addition of 1.3 at.% Ti raises the liquidus temperature from 630.755 C ( the melting point of pure Sb) to 680 C [51Now]. Although none of these points has been contradicted, four additional equilibrium phases have been identified since the [Hansen] compilation. This means that a considerably more complicated reaction scheme is needed to describe the equilibria for Ti-rich alloys. In the composition range Ti6Sb5 to Ti2.5Sb, alloys were found to decompose easily, either because of the presence of a high-temperature phase or because of a phase stabilized by oxygen [58Aue]. Ti3SbX is clearly an impurity-stabilized phase; it is irreversibly formed when alloys are melted in alumina crucibles [62Kje]. The homogeneity ranges of the compounds are narrow [51Now]. [75Don] reported the homogeneity range of TiSb2 as 66.2 to 67.1 at.% Sb, based on microscopic, X-ray, and density measurements. 51Now: H. Nowotny and J. Pesl, Monatsh. Chem., 82, 336-343 (1951) in German. 58Aue: H. Auer-Welsbach, H. Nowotny, and A. Kohl, Monatsh. Chem., 89, 154-159 ( 1958) in German. 60Dud: L.D. Dudkin and V.I. Vaidanich, Fiz. Tverd. Tela, 2(29), 404-405 (1960) in Russian; TR: Sov. Phys.-Solid State, 2, 377-378 (1960). 62Kje: A. Kjekshus, F. Gronvold, and J. Thorbjornsen, Acta Chem. Scand., 16, 1493-1510 (1962). 75Don: J.D. Donaldson, A. Kjekshus, D.G. Nicholson, and F. Rakke, J. Less- Common Met., 41, 255-263 (1975). Published in Phase Diagrams of Binary Titanium Alloys, 1987. Complete evaluation contains 1 figure, 1 table, and 10 references. 1