Фазовая диаграмма системы Ir-V

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Ir-V (Iridium-Vanadium) J.F. Smith The assessed Ir-V phase diagram was proposed by [67Gie]. Solidus temperatures are uncertain by с30 C, and the uncertainty of the congruent melting temperature of IrV3 is с50 C. The phase boundaries that are shown as solid lines were stated to have a compositional uncertainty of с1.5 at.%; no estimate was given for the compositional uncertainties associated with the dashed boundaries. Compositions for the liquids in the peritectic reactions are quite uncertain, but the other invariant compositions may have uncertainties as low as 1 at.%. Uncertainties in the temperatures are about с30 to 50 C. A number of reports confirm the existence of IrV3. Data concerning other regions in the system are comparatively sparse, but there is nothing incompatible with the assessed diagram. An indication of Ir3V was first noted [ 58Kna] by the observation of superlattice lines, and the nature of the ordered structure was subsequently determined [59Dwi]. [62Dwi] made a tentative identification of a phase in the central region as a tetragonally distorted CsCl structure. It is most likely, however, that they were looking at the tetragonal IrV1-x phase. IrV3 at ideal stoichiometry was tested to very low temperatures [63Mat, 70Spi] without finding superconductivity (Tc < 0.015 K), although V-deficient compositions exhibit superconductivity, with the transition temp- erature tending to increase with decreasing V content. [73Cox] reported that annealing of selected alloys resulted in essentially no change in the superconducting transition temperatures of nonstoichiometric alloys. 58Kna: A.G. Knapton, J. Inst. Met., 87, 28-32 (1958-59). 59Dwi: A.E. Dwight and P.A. Beck, Trans. Metall. Soc. AIME, 215, 976-979 (1959) . 62Dwi: A.E. Dwight and J.B. Darby, Jr., USAEC Rep. ANL-6677, 258-260 (1962); quoted in [Shunk]. 63Mat: B.T. Matthias, T.H. Geballe, and V.B. Compton, Rev. Mod. Phys., 35, 1- 22 (1963). 67Gie: B.C. Giessen, P.N. Dangel, and N.J. Grant, J. Less-Common Met., 13, 62- 70 (1967). 70Spi: P. Spitzli, R. Flukiger, F. Heiniger, A. Junod, J. Muller, and J.L. Staudenmann, J. Phys. Chem. Solids, 31, 1531-1537 (1970) in French. 73Cox: J.E. Cox and R.M. Waterstat, Phys. Lett. A, 46, 21-22 (1973). Published in Phase Diagrams of Binary Vanadium Alloys, 1989, and J. Alloy Phase Diagrams, 4(2), May 1988. Complete evaluation contains 1 figure, 3 tables, and 16 references. Special Points of the Ir-V System