Фазовая диаграмма системы Al-Sc

К оглавлению: Другие диаграммы (Others phase diargams)


Al-Sc (Aluminum-Scandium) K.A. Gschneidner, Jr. and F.W. Calderwood The assessed phase diagram for the Al-Sc system is based primarily on the work of [65Nau] and of the data of [73Dri] for the high Al-region of the diagram. Al and Sc are miscible in the liquid state at all concentrations. Four intermetallic compounds-Al3Sc, Al2Sc, AlSc, and AlSc2-exist. Al2Sc and AlSc melt congruently at 1420 and about 1300 C, respectively, whereas Al3Sc and AlSc2 are each the product of a peritectic reaction at 1320 and 1195 C, respectively. A eutectic occurs between Al2Sc and AlSc at 1150 C and ~45 at.% Sc, and another eutectic occurs between AlSc2 and Sc at 945 C and ~87 at.% Sc. Al3Sc forms a eutectic with Al at 655 C and 0.36 at.% Sc. Al3Sc has a cubic structure of the AuCu3-type; Al2Sc has a cubic structure of the Cu2Mg-type; and AlSc2 has a hexagonal structure of the InNi2-type. AlSc has a cubic CsCl- type structure. The solubility of Sc in (Al) at room temperature is <0.1 at.%, and the solubility of Al in (Sc) is about 4 at.% [65Nau]. In the assessed diagram, the solid solubility of Sc in (Al) varies from 0.186 at.% at 640 C to 0.033 at.% at 470 C [79Fuj]. 65Nau: O.P. Naumkin, V.F. Terekhova, and E.M. Savitskii, Izv. Akad. Nauk SSSR, Met., (4), 128 (1965); TR: Russ. Metall., (4), 176 (1965). 73Dri: M.E. Drits, E.S. Kadaner, T.V. Dobatkina, and N.I. Turkina, Izv. Akad. Nauk SSSR, Met., (4), 213 (1973); TR: Russ. Metall., (4), 152 (1973). 79Fuj: S. Fujikawa, M. Sugaya, H. Takei, and K. Hirano, J. Less-Common Met., 63, 87 (1979). Published in Bull. Alloy Phase Diagrams, 10(1), Feb 1989. Complete evaluation contains 1 figure, 1 table, and 19 references. 1