Фазовая диаграмма системы Cr-Ge

К оглавлению: Другие диаграммы (Others phase diargams)

Cr-Ge (Chromium-Germanium) A.B. Gokhale and G.J. Abbaschian The equilibrium phases of the Cr-Ge system are (1) the liquid, L; (2) the terminal solid solution, (Cr), with a maximum solubility of approximately 11 at.% Ge at the peritectic temperature of 1564 C; (3) the terminal solid solution, (Ge), with a maximum solid solubility of approximately 0.3 at.% Cr at the eutectic temperature of 895 C; (4) the cubic intermediate phase, Cr3Ge, which decomposes peritectically at 1564 C; (5) the tetragonal intermediate phase, Cr5Ge3, which decomposes peritectically at 1262 C and undergoes a polymorphic transformation at 1002 C; (6) the orthorhombic intermediate phase, Cr11Ge8, which decomposes peritectically at 1170 C; (7) the cubic intermediate phase, CrGe, which decomposes peritectically at 998 C; and (8) the tetragonal intermediate phase, Cr11Ge19, which decomposes peritectically at 928 C. The assessed phase diagram is based primarily on the data of [80God] and is supplemented with the work of [69Kal], [72Raw], and [78Kaw]. The maximum solid solubility of Ge in (Cr) is approximately 11 at.% at the peritectic temperature of 1564 C. The solubility decreases to about 4 at.% Ge at 700 C. The liquid solution is exothermic [79Shl], and the maximum heat evolution occurs at approximately 40 at.% Ge. Cr5Ge3 and Cr3Ge are Pauli paramagnetic, and CrGe and Cr11Ge19 obey the Curie- Weiss law above 200 and 280 K, respectively [80Kol]. 69Kal: G.I. Kalishevich, V.L. Zagryazskii, L.V. Shchipanova, N.N. Serebrennikov, and P.V. Gel'd, Russ. J. Phys. Chem., 43(1), 132-133 (1969). 72Raw: B. Rawal and K.P. Gupta, J. Less-Common Met., 27, 65-72 (1972). 78Kaw: I. Kawasumi, S. Konishi, M-Kubora, and M. Sakata, Jpn. J. Appl. Phys., 12(17), 2173-2174 (1978). 79Shl: A.-N. Shlapak, E.A. Beloboradova, I.V. Nikolaenko, and G.I. Batalin, Ukr.-Khim. Zh., 7(45), 670-672 (1979). 80God: D. Godat and P. Feschotte, J. Less-Common Met., 72(1), 7-22 (1980). 80Kol: M. Kolenda, J. Stoch, and A. Szytula, J. Magn. Magn. Mater., 20, 99-106 (1980). Published in Bull. Alloy Phase Diagrams, 7(5), Oct 1986. Complete evaluation contains 6 figures, 8 tables, and 15 references. Special Points of the Cr-Ge System