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JPEDAV (2006) 27:424-425 DOI: 10.1361/154770306X116496 1547-7037/$19.00 ©ASM International

Al-Be (Aluminum-Beryllium) H. Okamoto

The Al-Be phase diagram in [Massalski2] was redrawn from [1987Mur] (dashed lines in Fig. 1). [1994Oka] pointed out that the thermodynamic requirement is violated at the intersection between the (␤Be) liquidus and the (␣Be) liquidus in this diagram, and a slight change in the intersection position would solve the problem. This problem was induced when the allotropic transformation temperature of Be was raised from 1254 °C in the original diagram of [1983Mur] to 1270 °C in [1987Mur]. Using essentially the same experimental phase boundary data as [1983Mur], [2004Pan] calculated the Al-Be phase diagram, as shown with solid lines in Fig. 1. The allotropic transformation temperature of Be is assumed to be 1254 °C. Naturally, the problem of [1987Mur] is nonexistent in the calculated diagram. The Al-rich corner is enlarged in Fig. 2. However, according to more careful measurements by [2000Kle], the allotropic transformation temperature of Be is 1269 ± 1 °C, which is in agreement with [1987Mur] (the melting temperature is 1283 ± 2 °C) (see [2000Oka]).

Fig. 1

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Therefore, the Be corner of the calculated diagram needs a fine adjustment. References 1983Mur: J.L. Murray and D.J. Kahan, The Al-Be (AluminumBeryllium) System, Bull. Alloy Phase Diagrams, 1983, 4(1), p 50-55 1987Mur: J.L. Murray and D.J. Kahan, The Al-Be (AluminumBeryllium) System, Phase Diagrams of Binary Beryllium Alloys, H. Okamoto and L. Tanner, Ed., ASM International, 1987, p 9-14 1994Oka: H. Okamoto and T.B. Massalski, Binary Alloy Phase Diagrams Requiring Further Studies, J. Phase Equilibria, 1994, 15(5), p 500-521 2000Kle: H. Kleykamp, Thermal Properties of Beryllium, Thermochim. Acta, 2000, 345(2), p 179-184 2000Oka: H. Okamoto, Be (Beryllium), J. Phase Equilibria, 2000, 21(6), p 570 2004Pan: Z. Pan, Y. Du, B.Y. Huang, Y. Liu, and R.C. Wang, A Thermodynamic Description of the Al-Be System: Modeling and Experiment, Calphad, 2004, 28, p 371-378

Al-Be phase diagram

Journal of Phase Equilibria and Diffusion Vol. 27 No. 4 2006

Supplemental Literature Review: Section III

Fig. 2 Al corner of the Al-Be phase diagram

Journal of Phase Equilibria and Diffusion Vol. 27 No. 4 2006

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