Фазовая диаграмма системы Co-Ni

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Co-Ni (Cobalt-Nickel) T. Nishizawa and K. Ishida Equilibrium between the solid and liquid phases in the assessed diagram of the Co-Ni system is substantially the same as the diagram from [Hansen]. Solidification takes place in a temperature interval of only a few degrees. Recent thermodynamic calculations [70Hay, 73Kau, 78Kau, 79Tom, 82Has] show that the temperature interval is even less wide (e.g., about 0.3 C at 50 at.% Ni), which indicates that the liquid and solid solutions may be described as nearly thermodynamically ideal. Co and Ni exhibit complete solid solubility in the (aCo,Ni) phase at temperatures between the solidus and the solvus of the a (fcc) = e ( cph) transformation temperature that extends from pure Co. The boundaries of the two-phase region are not well established because of the difficulties in achieving equilibrium at low temperatures. The maximum solubility of Ni in the e phase is estimated to be 5 at.% at 250 C. The approximate allotropic transformation temperature in pure Co is 422 C [68Ada]. Pure Co and Ni are both ferromagnetic, with Curie temperatures of 1121 and 361 C, respectively. The Curie temperature of Co is lowered continuously by alloying with Ni [74Ore]. 68Ada: R. Adams and C. Altstetter, Trans. AIME, 242, 139 (1968). 70Hay: F.H. Hayes, F. Muller, and O. Kubaschewski, J. Inst. Met., 98, 20 (1970) . 73Kau: L. Kaufman and H. Nesor, Z. Metallkd., 64, 249 (1973). 74Ore: J. Orehotski and K. Schroder, Phys. Condens. Matter, 17, 37 (1974). 78Kau: L. Kaufman and H. Nesor, Calphad, 2, 81 (1978). 79Tom: J. Tomiska, H. Nowotny, L. Erdelyi, and A. Neckel, Ber. Bunsenges. Phys. Chem., 83, 1035 (1979). 82Has: M. Hasebe, K. Oikawa, and T. Nishizawa, J. Jpn. Inst. Met., 46, 584 ( 1982). Published in Phase Diagrams of Binary Nickel Alloys, 1991, and Bull. Alloy Phase Diagrams, 4(4), Dec 1983. Complete evaluation contains 6 figures, 2 tables, and 90 references. 1