Фазовая диаграмма системы Al-Ni

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Al-Ni (Aluminum-Nickel) M.F. Singleton, J.L. Murray, and P. Nash The assessed Al-Ni phase diagram consists of two fcc solid solutions, (Al) and (Ni), and the intermetallic phases AlNi3, AlNi, Al3Ni2, Al3Ni, and Al3Ni5. The present diagram is very similar to that of [Hansen], with modifications based on the work of [84Rob]. It is also based on review of pertinent experimental data [23Bin, 34Fin, 37Ale, 41Sch, 42Phi, 63Sch, 69Ras, and 77Lit]. The melting points of the pure metals are taken from [Melt]. Thermodynamic calculations have been performed to reconcile experimental data with the phase diagram. In the present calculations, it was not possible to reproduce the liquidus and solidus of AlNi on the Ni-rich side of stoichiometry. In the calculated phase diagram, the homogeneity range of AlNi on the Ni-rich side was found to be less than that observed experimentally. The solid solubility of Ni in (Al) is very limited, but was reported to decrease from 0.11 at.% Ni at the eutectic temperature to 0.01 at.% Ni at 500 C [34Fin]. (Ni) dissolves Al in solid solution up to a maximum of 21.2 at.% at the Ni-rich eutectic temperature of 1385 C [37Ale]. In the supersaturated ( Ni) solution, the first precipitates of L12 AlNi3 (g›) are formed coherent with the fcc matrix. Rapid quenching (105 to 108 C/s) from the melt of an Al-rich Ni alloy extends the solid solubility limit of Ni in (Al) from 0.1 at.% Ni to as much as 7.7 at. % Ni. The hardness of the resulting supersaturated solid solution was found to be composition dependent (increasing with Ni content) and became unstable on annealing at 150 C. Vapor quenching increased the metastable solid solubility of Ni in (Al) to 20. 9 at.% Ni. Instability of getter-sputtered Al-Ni supersaturated solid solution was reported upon annealing at temperatures above 300 to 400 C, with formation of an (Al) + Al3Ni structure. Quenching of Ni-rich (~64 at.% Ni) NiAl from high temperatures (1200 C) leads to the formation of an ordered, fct, twinned martensite. The martensite transformation in AlNi satisfies certain prerequisites for shape memory behavior: (1) the transformation is thermoelastic, (2) the parent and martensite phases are ordered, and (3) the martensite is internally twinned. 23Bin: K.E. Bingham and J.L. Haughton, J. Inst. Met., 29, 80 (1923). 34Fin: W.L. Fink and L.A. Willey, Trans. AIME, 111, 293-303 (1934). 36Man: C. Manders, Ann. Phys., 5, 193-195 (1936) in French. 37Ale: W.O. Alexander and N.B. Vaughan, J. Inst. Met., 61, 247-260 (1937). 37Mar: V. Marian, Ann. Phys., 7-8, 487-489 (1937) in French. 41Sch: J. Schramm, Z. Metallkd., 33, 347-355 (1941) in German. 42Phi: H.W.L. Phillips, J. Inst. Met., 68, 28-30 (1942). 63Sch: J.D. Schobel and H.H. Stadelmaier, Z. Metallkd., 53, 326-328 (1963). 69Ras: R.K. Rastogi and V.J. Ardel, Acta Metall., 17, 595-602 (1969). 77Lit: V.S. Litvinov and A.A. Arkhangel'skaya, Fiz. Met. Metalloved., 43(5), 1044-1051 (1977) in Russan; TR: Phys. Met. Metallogr. (USSR), 43(5), 127-133 ( 1977). 84Rob: I.M. Robertson and C.M. Wayman, Metallography, 17, 43-55 (1984). Published in Phase Diagrams of Binary Nickel Alloys, 1991. Complete evaluation contains 8 figures, 4 tables, and 50 references. Special Points of the Al-Ni System