Фазовая диаграмма системы Ge-Mo

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Ge-Mo (Germanium-Molybdenum) R.W. Olesinski and G.J. Abbaschian The assessed Ge-Mo phase diagram at 1 atm presents the following stable phases: (1) the liquid, L; (2) the solid solution, (Ge), with negligible solubility of Mo; (3) the terminal solid solution, (Mo), with a maximum solubility of ~5 at.% at the peritectic temperature of 1800 C; (4) the cubic intermediate phase, aGe2Mo; which decomposes peritectically at 1080 C; (5) the tetragonal intermediate phase, Ge23Mo13, which decomposes peritectically around 1520 C; ( 6) the hexagonal intermediate phase, Ge3Mo5, which decomposes peritectically at 1730 C; and (7) the cubic intermediate phase, GeMo3, which decomposes peritectically around 1800 C. The assessed phase diagram is based on the experimental data of [63Ste]. The only complete determination of the Ge-Mo phase diagram was attempted by [ 63Ste] using melting point measurements corroborated with X-ray and metallography techniques. Mo-rich samples were additionally examined by means of conductivity and harness measurements. The solid solubility of Mo in (Ge) is probably negligible [63Ste]. X-ray measurements of Mo-rich alloys quenched from 1750 C implied that the maximum concentration of Ge in (Mo) was ~5 at.% Ge at that temperature, which was assumed to be the temperature of GeMo3 peritectic transformation; no other data on (Mo) composition are available. The present evaluators have assessed the (Mo) phase boundary based on the assumption of the Henrian character of the solution and have adopted 5 at.% Ge as the maximum solubility of Ge in (Mo) at the peritectic temperature estimated at 1800 C. The high-pressure tetragonal bGe2Mo was obtained at atmospheric pressure upon rapid quenching of samples containing less than 40 at.% Mo from 1350 C [53Sea] . Further investigations [59Pea] confirmed the metastable character of the bGe2Mo at low pressures; the b phase is the equilibrium form of Ge2Mo at high pressures. Crystallization of Ge-Mo amorphous films was investigated by [70Bos] by electron diffraction and resistivity methods. The metal films were deposited as alternate layers each less than 30 nm thick. The amorphous-to-crystalline transition temperature was reported to be above 300 C. 53Sea: A.W. Searcy and R.J. Peavler, J. Am. Chem. Soc., 75, 5657-5659 (1953). 59Pea: R.J. Peavler and C.G. Beck, Jr., J. Phys. Chem., 63, 2058-2059 (1959). 63Ste: P. Stecher, F. Benesovsky, and H. Nowotny, Monatsch. Chem., 94, 1154- 1162 (1963) in German. 70Bos: J.R. Bosnell and U.C. Voisey, Thin Solid Films, 6, 161-166 (1970). Published in Bull. Alloy Phase Diagrams, 8(1), Feb 1987. Complete evaluation contains 2 figures, 3 tables, and 16 references. Special Points of the Ge-Mo System