Фазовая диаграмма системы B-Ge

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B-Ge (Boron-Germanium) R.W. Olesinski and G.J. Abbaschian A qualitative representation of the Ge-B phase diagram, which is a slightly modified version of the diagram given by [70Bid], indicates: (1) a monotectic reaction around 1900 to 2000 C; (2) a reaction, possibly peritectic, at a temperature very close to the melting point of Ge (938.3 C [Melt]); and (3) the melting point of B at 2092 C [Melt]. The available literature on the Ge-B phase diagram is limited. [70Bid] determined general features of the diagram by X-ray diffraction, metallographic and thermal analyses, and electron microprobe studies of both sintered and melted alloys. He evaluated the monotectic composition to be between 70 and 90 at.% B and the monotectic temperature around 2000 C. [70Bid] also suggested the possibility that the reaction at a temperature very close to the melting point of Ge is eutectic, involving almost pure liquid Ge. However, the distribution coefficient measurements of [53Hal], [56Bri], and [ 70Edw] show k0 > 1. Therefore, the present evaluators have proposed that the transformation is peritectic. The solubility of Ge in solid (B) was reported to be small, reaching a maximum at the monotectic temperature. The solubility of B in (Ge) is reported to be negligible at all temperatures. 53Hal: R.N. Hall, J. Phys. Chem., 57, 836-839 (1953). 56Bri: H.E. Bridgers and E.D. Kolb, J. Chem. Phys., 25, 648-650 (1956). 70Bid: L.R. Bidwell, J. Less-Common Met., 20, 19-27 (1970). 70Edw: W.D. Edwards, J. Electrochem. Soc., 117, 1062-1065 (1970). Published in Bull. Alloy Phase Diagrams, 5(5), Oct 1984. Complete evaluation contains 2 figures, 2 tables, and 12 references. 1