Фазовая диаграмма системы Al-Sm

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Al-Sm (Aluminum-Samarium) K.A. Gschneidner, Jr. and F.W. Calderwood Although the Al-Sm system has been studied extensively, a complete phase diagram including the liquidus in the Sm-rich region is not available. The assessed phase diagram is based on review of the work of [65Bus], [67Bus], and [71Bus]. The lack of data on the liquidus curves in this system at high temperatures is due to the low boiling point and high vapor pressure of Sm, which renders control of the composition of samples difficult. No data were found for the solubility at either end of the phase diagram. AlSm2, the Sm-rich compound, has orthorhombic Co2Si-type structure, and the equimolar compound, AlSm, has orthorhombic AlEr-type structure. X-ray data also confirmed the existence of an Al2Sm compound that has cubic Cu2Mg-type symmetry, and Al2Sm, which has hexagonal symmetry of the Ni3Sn type. Quenching of an 80 at.% Al composition from above 1055 C produced a tetragonal Al11Sm3 compound that melts on cooling, forming a mixture of solid Al3Sm and Al-rich liquid. [67Bus] reported that this orthorhombic Al11La3-type phase is a metastable form, stabilized by some unidentified impurity, or cooled beyond the metastable transition point without decomposition. 65Bus: K.H.J. Buschow and J.H.N. van Vucht, Philips Res. Rep., 20, 15 (1965). 67Bus: K.H.J. Buschow and J.H.N. van Vucht, Philips Res. Rep., 23, 223 (1967). 71Bus: K.H.J. Buschow and A.S. Van der Goot, J. Less-Common Met., 24, 117 ( 1971). Published in Bull. Alloy Phase Diagrams, 10(1), Feb 1989. Complete evaluation contains 1 figure, 1 table, and 17 references. 1