Фазовая диаграмма системы Ge-Y

К оглавлению: Другие диаграммы (Others phase diargams)

Ge-Y (Germanium-Yttrium) A.B. Gokhale and G.J. Abbaschian The assessed Y-Ge phase diagram is taken from the work of [72Sch], who carried out a complete determination of the phase equilibria in the system. The system is characterized by two eutectics, seven peritectics, a metatectic (inverse peritectic), two eutectoids, and two allotropic transformations. [72Sch] also determined that the intermediate phases Y5Ge3, Y5Ge4, Y11Ge10, YGe, Y2Ge3, Y3Ge5, YGe2, and Y2Ge7 exist. Y5Ge3 was found to melt congruently, whereas the other phases form through peritectic reactions at temperatures decreasing with increasing Ge content. According to [72Sch], none of the intermediate phases exhibited a homogeneity range. Consequently, they are shown as stoichiometric in the assessed diagram. The maximum solubility of Y in (Ge) is less than 0.5 at.% at the eutectic temperature (820 C) and almost nil at 600 C [72Sch]. The maximum solubility of Ge in (Y) is below 1.0 at.% at the eutectic temperature (1280 C) and ~0.3 at.% at 800 C [72Sch]. The system exhibits a metatectic reaction near the terminal solid solution, (Y) . According to [72Sch], the reaction can be interpreted as a decrease in the allotropic transformation temperature of Y from 1478 to 1460 C, due to the addition of Ge. Y5Ge3 and YGe were shown to be Pauli paramagnets by [67Bus] and [66Bus], respectively. [69Rud] showed that electrical resistivity of the phases decreases with increasing temperature. 66Bus: K.H.J. Buschow and J.F. Fast, Phys. Status Solidi, 16, 467-473 (1966). 66Tha: A.G. Tharp, G.S. Smith and Q. Johnson, Acta Crystallogr., 20, 583-585 ( 1966). 67Bus: K.H.J. Buschow and J.F. Fast, Phys. Status Solidi, 21, 593-600 (1967). 67Smi: G.S. Smith, A.G. Tharp, and Q. Johnson, Acta Crystallogr., 22, 940-943 ( 1967). 69Rud: B.M. Rud, T.G. Kutsenok, and Yu.B. Paderno, Poroshk. Metall., 76(4), 34- 37 (1969) in Russian; TR: Sov. Powder Metall. Met. Ceram., 76(4), 284-287 ( 1969). 72Sch: F.A. Schmidt, O.D. McMasters, and O.N. Carlson, J. Less-Common Met., 26( 1), 53-70 (1972). 83Bru: V.A. Bruskov, O.I. Bodak, V.K. Pecharskii, E.I. Gladyschevskii, and L.A. Maratova, Kristallografiya, (28), 260-263 (1983) in Russian; TR: Sov. Phys. Crystallogr., (28), 151-153 (1983). Published in Bull. Alloy Phase Diagrams, 9(1), Feb 1988. Complete evaluation contains 2 figures, 3 tables and 27 references. Special Points of the Y-Ge System