Фазовая диаграмма системы Lu-V

К оглавлению: Другие диаграммы (Others phase diargams)

Lu-V (Lutetium-Vanadium) J.F. Smith and K.J. Lee Experimental data concerning phase equilibria in the Lu-V system are sparse. The phase diagram for the Lu-V system was calculated with the assumption that the general features of the diagram and the interaction parameters are comparable to the other trivalent rare earths of lower atomic number. Data for the Gibbs energy of melting of cph Lu were taken from [Gschneidner], and for the entropy of melting of bcc Lu from [75Gsc]. This entropy of melting also produced an enthalpy of melting for bcc Lu when combined with a melting temperature obtained by extrapolation of the melting points of the lighter bcc rare earths. The Gibbs energy of melting bcc V was taken from [81Smi] and the Gibbs energy of melting of cph V from [70Kau]. Initial interaction parameters were estimated by the Miedema approach [80Deb, 83Mie, 83Nie]. These initial interaction parameters were refined from the trends among the plots of the interaction parameters vs atomic number that had been found for other trivalent lanthanons. The magnitudes of these refined interaction parameters differed by less than 10% from the Miedema approximations [80Deb, 83Mie, 83Nie] . [61Gsc] reported unpublished work by R. Beck indicating the existence of a region of liquid immiscibility in the Lu-V system. This is consistent with the observation of liquid immiscibility in all other systems involving V with Y or a trivalent lanthanon element. 61Gsc: K.A. Gschneidner, Jr., Rare Earth Alloys, D. Van Nostrand Co., Inc., New York, 331 (1961). 70Kau: L. Kaufman and H. Bernstein, Computer Calculation of Phase Diagrams, Academic Press, New York, 184 (1970). 75Gsc: K.A. Gschneidner, Jr. J. Less-Common Met., 43, 179-189 (1975). 80Deb: R.R. deBoer, R. Boom, and A.R. Miedema, Physica, 101B, 294-319 (1980). 81Smi: J.F. Smith, Bull. Alloy Phase Diagrams, 2(1), 40-41 and 2(2), 172 (1981) . 83Mie: A.R. Miedema and A.K. Niessen, Calphad, 7, 27-36 (1983). 83Nie: A.K. Niessen, F.R. deBoer, R. Boom, P.F. deChatel, W.C.M. Mattens, and A.R. Miedema, Calphad, 7, 51-70 (1983). Published in Phase Diagrams of Binary Vanadium Alloys, 1989. Complete evaluation contains 1 figure, 2 tables, and 9 references. Special Points of the Lu-V System