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ection II: Phase Diagram Evaluations

Al-Sb-Y (Aluminum-Antimony-Yttrium) V. Raghavan

Muraveva et al. [1971Mur] reported a partial isothermal section of this system at 500 °C up to 33.3 at.% Y. Recently, [2003Zen] determined an isothermal section at 527 °C (800 K) for the entire composition range. No ternary compounds were found.

Binary Systems The Al-Sb phase diagram has the equiatomic compound AlSb, which melts congruently at 1,058 °C. The Al-Y phase diagram [2006Liu, Massalski2] has the following intermediate phases: aAl3Y (D019, Ni3Sn-type hexagonal), bAl3Y (BaPb3-type rhombohedral), Al2Y (C15, MgCu2-type cubic), AlY (Bf, CrB-type orthorhombic), Al2Y3 (Al2Zr3type tetragonal), and AlY2 (C23, Co2Si-type orthorhombic). The Sb-Y phase diagram [Massalski2] depicts the following intermediate phases: Y3Sb (PTi3-type tetragonal), Y5Sb3 (D88, Mn5Si3-type hexagonal), Y4Sb3 (D73, P4Th3-type cubic, stable between 2,120 and 1,660 °C), and YSb (B1, NaCl-type cubic).

Ternary Isothermal Section With starting metals of 99.8% Al, 99.9% Sb and 99.7% Y, [2003Zen] arc-melted under Ar atm 99 alloy compositions. The samples were given a final anneal at 527 °C (800 K) for 200 h and quenched in water. The phase equilibria were studied using x-ray powder diffraction and scanning electron microscope with energy dispersive analyzer. The isothermal section at 527 °C (800 K) constructed by [2003Zen] is shown in Fig. 1. The metastable phase AlY3 indicated by [2003Zen] is replaced tentatively with AlY2 in Fig. 1. Y3Sb5 dissolves up to 27 at.% Al at constant Y content. The third component solubility in the other binary phases is negligible. No ternary compounds were found. References 1971Mur: A.M. Muraveva, O.S. Zarechnyuk, and E.I. Gladyshevskii, The Systems Y-Al-Si (Ge,Sb) in the Range 0-0.33.3 at.% Y, Neorg. Mater., 1971, 7(1), p 38-40 in Russian; TR: Inorg. Mater., 1971, 7(1), p 34-36

Fig. 1 Al-Sb-Y isothermal section at 527 °C (800 K) [2003Zen]. Narrow two-phase regions are omitted

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Phase Diagram Evaluations: Section II 2003Zen: L. Zeng and S. Wang, The 800 K Isothermal Section of the Y-Al-Sb Phase Diagram, J. Alloys Compd., 2003, 351, p 176-179

2006Liu: S. Liu, Y. Du, H. Xu, C. He, and J.C. Schuster, Experimental Investigation of the Al-Y Phase Diagram, J. Alloys Compd., 2006, 414, p 60-65

Journal of Phase Equilibria and Diffusion Vol. 29 No. 2 2008

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