Фазовая диаграмма системы Ni-V

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Ni-V (Nickel-Vanadium) J.F. Smith, O.N. Carlson, and P.G. Nash The Ni-rich portion of the Ni-V assessed diagram is based primarily on the work of [52Pea], whereas the V-rich end is largely based on the results of [ 70Ste]. The Ni in both of these investigations was of greater than 99.9% purity. The V in the latter investigation was of 99.95% purity, whereas that of [52Pea] varied between 99.3% and 99.9+% purity. The Curie temperature of ( Ni) falls with the addition of V [37Mar]. [71Mor] used electrical resistivity and electron diffraction techniques to identify an ordered fct phase of Ni8V stoichiometry. This phase forms from the Ni-rich solid solution by an order-disorder reaction. [52Pea] placed the Ni-rich boundary of the s phase at 55 at.% V and the Ni- poor boundary at greater than 65 at.% V. [55Nev] found the s phase to become ferromagnetic at low temperatures; specifically, a 64.2 at.% V alloy was found to have a Curie temperature of 52 K. There appears to be convincing evidence for the existence of a phase with an ideal stoichiometry of NiV3, but which actually occurs with a V-rich stoichiometry. The fact that not all investigators have found the phase indicates that its formation may be influenced by factors such as kinetics or impurities, which tend to defeat binary thermodynamic equilibrium. NiV3 crystallizes with the Cr3Si-type structure. In splat-quenching experiments on Ni-V alloys, the (Ni) solid solution range was extended to ~52 at.% V with no detectable difference within the range of the cooling rates of the experiments (105 to 109 C/s). Above 52 at.% V, there appeared to be an abrupt change to a metastable bcc structure that was isostructural with and apparently an extension of the W-type structure of the ( V) terminal solid solution. Occurrence of the s phase was completely suppressed at higher cooling rates of 107 to 108 C/s, but traces of s phase were observed to coexist with the metastable bcc phase in splats cooled at slower cooling rates of 105 to 106 C/ s. 37Mar: V. Marian, Ann. Phys., 7, 459-527 (1937). 52Pea: W.B. Pearson and W. Hume-Rothery, J. Inst. Met., 80, 641-648 (1952). 55Nev: M.V. Nevitt and P.A. Beck, Trans. AIME, 203, 669-674 (1955). 70Ste: E.R. Stevens and O.N. Carlson, Metall. Trans., 1, 1267-1271 (1970). 71Mor: H.A. Moreen, R. Taggart, and D.H. Polonis, J. Mater. Sci., 6, 1425-1432 (1971). Published in Phase Diagrams of Binary Nickel Alloys, 1991, Phase Diagrams of Binary Vanadium Alloys, 1989, and Bull. Alloy Phase Diagrams, 3(3), Dec 1982. Complete evaluation contains 1 figure, 3 tables, and 35 references. 1