Фазовая диаграмма системы Au-Tb

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Au-Tb (Gold-Terbium) K.A. Gschneidner, Jr., F.W. Calderwood, H. Okamoto, and T.B. Massalski The Tb-Au system is characterized by the existence of six intermetallic compounds, which exist in a total of seven structure types. Although structural data have been reported for these compounds, the phase diagram has not been determined experimentally for the entire system. [71Mcm] studied the crystal structures of intermetallic compounds of the trivalent lanthanides-Au systems and reported that Tb2Au crystallizes in the orthorhombic Co2Si-type structure. Two structure types have been observed for TbAu. [71Mcm] reported that a needle of this composition, heat treated at 900 C and subjected to Co radiation, had an orthorhombic structure of the CrB-type. [63Cha] splat cooled TbAu and reported a cubic structure of the CsCl type. [71Mcm] reported the melting temperature of TbAu to be 1623 с 10 C. They did not detect the CsCl = CrB transformation temperature, but stated that it exists. TbAu2 has the tetragonal structure of the MoSi2-type. [71Mcm] reported that the heavy lanthanides, including Tb, form REAu3 compounds that have orthorhombic Cu3Ti-type structures. Controversy exists regarding the stoichiometry of a hexagonal RE-Au phase having composition between 75 and 80 at.% Au. [69Don] reported the hexagonal structure of Ag3Pu-type for a "TbAu3" compound that had lattice spacings in fair agreement with those that [71Mcm] reported for hexagonal Tb14Ag51 of the Ag51Gd14 type. The small variation in the parameter has led the present evaluators to conclude that a slight solubility range exists for this phase. A TbAu6 phase was reported by [71Mcm] in needles that had been heat treated at 750 C for three days. Powder patterns indicated a tetragonal unit cell. [65Rid] investigated the solid solubility of Tb in (Au) and reported a solubility of 1.5 at.% Tb in (Au) at the eutectic temperature of 809 C. 63Cha: C.C. Chao, H.L. Luo, and P. Duwez, Jr., J.Appl. Phys., 34, 1971 (1963). 65Rid: P.E. Rider, K.A. Gschneidner, Jr., and O.D. McMasters, Trans. AIME, 233, 1488 (1965). 69Don: C.Donolato and S. Steeb, J. Less-Common Met., 18, 442, (1969). 71Mcm: O.D. McMasters, K.A. Gschneidner, Jr., G. Bruzzone, and A. Palenzona, J. Less-Common Met., 25, 135 (1971). Published in Phase Diagrams of Binary Gold Alloys, 1987. Complete evaluation contains 3 figures, 2 tables, and 15 references. 1