Al-B-Gd (Aluminum-Boron-Gadolinium)

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JPEDAV (2007) 28:444–445 DOI: 10.1007/s11669-007-9134-6 1547-7037 ASM International

Al-B-Gd (Aluminum-Boron-Gadolinium) V. Raghavan

[1994Mik] determined an isothermal section at 600 C for this ternary system, which depicts no ternary compounds.

GdB4 (D1e, ThB4-type tetragonal), Gd2B5 (Sm2B5-type monoclinic), and GdB2 (C 32, AlB2-type hexagonal).

Ternary Isothermal Section

Binary Systems There are two intermediate phases in the Al-B system: AlB2 (C32, AlB2-type hexagonal) and AlB12 (AlB12-type tetragonal). The Al-Gd system [2000Sac, Massalski2] has the following intermediate phases: GdAl3 (D019, Ni3Sn-type hexagonal), GdAl2 (C15, MgCu2-type cubic), GdAl (ErAltype orthorhombic), Gd3Al2 (Zr3Al2-type tetragonal), and Gd2Al (C23, Co2Si-type orthorhombic). The B-Gd phase diagram [Massalski2] depicts the following compounds: GdB66 (YB66-type cubic), GdB6 (D21, CaB6-type cubic),

With starting materials of purity ‡99.5 mass% purity, [1994Mik] arc-melted or sintered 45 ternary alloys. The alloys were annealed at 600 C for not less than 500 h and quenched in water. The phase equilibria were studied by X-ray powder diffraction. The isothermal section at 600 C constructed by [1994Mik] is shown in Fig. 1. No ternary compounds were found. GdB2 is not stable at 600 C. The phase equilibria involving AlB2, AlB12, and GdB66 were not determined. No positive indication of the existence of the compound GdAlB14 could be obtained [1994Mik].

Fig. 1 Al-B-Gd isothermal section at 600 C [1994Mik]. Thin two-phase regions are omitted

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Journal of Phase Equilibria and Diffusion Vol. 28 No. 5 2007

Phase Diagram Evaluations: Section II References 1994Mik: S.I. Mikhalenko, N.F. Chaban, and Yu.B. Kuzma, Reaction of Rare-Earth Metals with Boron and Aluminum, Porosh. Metall., 1994, (11-12), p 27-31, in Russian; TR:

Powder Metall. Met. Ceramics, 1994, 33(11-12), p 584587 2000Sac: A. Saccone, A.M. Cardinale, S. Delfino, and R. Ferro, Gd-Al and Dy-Al Systems: Phase Equilibria in the 0 to 66.7 at.% Composition Range, Z. Metallkd., 2000, 91(1), p 17-23

Journal of Phase Equilibria and Diffusion Vol. 28 No. 5 2007

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