Фазовая диаграмма системы Sr-Ti

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Sr-Ti (Strontium-Titanium) J.L. Murray [78Ali] measured solubilities of Ti in liquid Sr at several temperatures and found them to be very low. [78Ali] held Ti isothermally in liquid Sr for 1.5 to 3 h under pressure in helium. The solubility of Ti in liquid Sr was determined by chemical analysis of several samples of the liquid layer. Microstructures were also reported to have been examined. Alloys were prepared from "degassed Ti used as a getter, and ... strontium of analytical purity." [78Ali] reported solubilities of Ti in liquid Sr and Ba at 800, 900, and 1000 C in the form of equations and figures. However, values of the two do not correspond. Assuming the figures to be correctly labeled, the present evaluator concluded that the equations for Sr and Ba had been reversed and that in the equation temperature was given in C and composition x in atomic fraction of Sr. Therefore, the equation for the solubility is log x = -2.0265 - 1279/T. Based on the experimental liquid solubility data, [78Ali] estimated solubilities of Sr in (aTi) and (bTi) at 882 C as 0.019 and 0.0059 at.% Sr, respectively, using a method which was not described. These values are shown in the assessed phase diagram, but it is not recommended that a great deal of reliance be placed on solid solubility values obtained by an unknown method from unconfirmed liquid solubility data. 78Ali: F.N. Alidzhanov, A.V. Vakhobov, and T.D. Dushanbe, Izv. Akad. Nauk SSSR, Met., (2), 223-224 (1978); TR: Russ. Metall., (2), 177-178 (1978). Published in Phase Diagrams of Binary Titanium Alloys, 1987. Complete evaluation contains 2 figures, 2 tables, and 2 references. Special Points of the Ti-Sr System