Фазовая диаграмма системы Al-Au

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Al-Au (Aluminum-Gold) J.L. Murray, H. Okamoto, and T.B. Massalski Nearly all of the important features in the assessed Al-Au phase diagram are based on the work of [00Hey]. The equilibrium phases are (1) the fcc terminal solid solution, (Al); (2) the CaF2-type Al2Au; (3) the monoclinic AlAu; (4) the MoSi2-type gAlAu2, with two low-temperature polymorphic forms of distorted MoSi2-type structures, bAlAu2 and aAlAu2; (5) the rhombohedral Al2Au5; (6) the bcc aAlAu4; (7) the distorted bMn-type aAlAu4, which is a low-temperature polymorphic form of bAlAu4; and (8) the fcc terminal solid solution, (Au). The stoichiometry of the phase formed peritectically at 575 C has been claimed to be Al2Au5 or Al3Au8; however, thermal analysis data of [00Hey] indicate that Al2Au5 is more likely [Hansen]. [74Fuj] reported the solid solubility of Au in (Al) to be 0.048 at.% 640 C. The maximum solid solubility of Al in (Au) is ~16 at.% at 545 C [Hansen]. The maximum solubility of Au in (Al) can be increased from the equilibrium value of 0.06 at.% Au to 0.35 at.% Au by using rapid solidification [69Tod]. A large age-hardening effect is found in Al-rich alloys. 00Hey: C.T. Heycock and F.H. Neville, Philos. Trans. R. Soc. (London) A, 194, 201-232 (1900). 69Tod: T. Toda and R. Maddin, Trans. Metall. Soc. AIME, 245(5), 1045-1054 ( 1969). 74Fuj: S. Fujikawa and K. Hirano, J. Jpn. Inst. Met., 38(10), 929-936 (1974) in Japanese. Published in Bull. Alloy Phase Diagrams, 8(1), Feb 1987, and Phase Diagrams of Binary Gold Alloys, 1987. Complete evaluation contains 4 figures, 7 tables, and 63 references. 1