Фазовая диаграмма системы Fe-Pt

К оглавлению: Другие диаграммы (Others phase diargams)

Fe-Pt (Iron-Platinum) H. Okamoto The assessed phase diagram for the Fe-Pt system is based on the experimental work of [07Isa], [34Fal], [35Gra], [38Fal], [38Mar], [50Kus], [57Ber], [59Buc], [63Sun], [73Miz], [80Cha], and [81Mat]. The equilibrium phases are: (1) the liquid, L; (2) the bcc terminal solid solution (dFe); (3) the fcc continuous solid solution, (gFe, Pt) or g; (4) the bcc terminal solid solution, (aFe); (5) cubic AuCu3-type Fe3Pt; (6) tetragonal AuCu-type FePt; (7) cubic AuCu3-type FePt3; (8) the bct martensite phase, a›; and (9) the fct martensite phase, g›. The phase boundaries between the solid phases are uncertain. The melting points of dFe and Pt are 1538 and 1769.0 C, respectively [Melt]. The minimum melting temperature of (gFe, Pt) and the corresponding composition could not be determined experimentally, due to the very "shallow" liquidus and solidus [59Buc]. The maximum solubility of Pt in (dFe) is 2.3 at.% [59Buc]. The boundaries of (aFe) in the assessed diagram represent the (aFe) = g transition on heating and the g = (aFe) transition on cooling. The equilibrium g/[(aFe) + g] and [(aFe) + g]/(aFe) boundaries are unknown. [50Kus] showed the existence of AuCu3-type ordered Fe3Pt and placed the maximum transition temperature at about 840 C. [57Ber] suggested that the temperature should be lower by about 100 C. Out of two data points of [80Cha] , one is in agreement with [50Kus] and the other with [57Ber]. The assessed solvus of Fe3Pt is a tentative compromise of these conflicting data, and should be regarded as schematic. [74Mei] measured the change of Curie temperature (TC) of 90 to 99 at.% Pt alloys under pressure up to 170 kbar. The results were given in terms of volume coefficients of the Curie temperature vs the Curie temperature ( explicit values were not given). The TC of aFe is 770 C [82Swa]. The composition dependence of TC of (aFe) is not well defined. It is nearly constant [34Fal, 50Kus] or increases with increasing Pt content [07Isa]. The composition dependence of TC of disordered g measured by [35Gra], [50Kus], [57Ber], and [73Miz] is fairly consistent. The discontinuity of TC at the phase boundaries between Fe3Pt and FePt is not clear, due to the scatter in the experimental data. [79Sum] studied the relationship between the invar effect and the magnetic properties of Fe3Pt in detail. [35Gra] and [50Kus] considered all of the ordered phase on the Pt-rich side to belong to FePt. Because ordered FePt3 is antiferromagnetic, extrapolation of the phase boundaries between FePt and FePt3 appears to contradict the TC curve. Further clarification of the phase boundaries and TC is needed. FePt3 is paramagnetic [50Kus] and becomes antiferromagnetic at low temperatures [58Cra]. There are two types of antiferromagnetic structures, with different N‚el temperatures [63Bac1]. Disordered FePt3 is ferromagnetic, and the antiferromagnetism occurs to increasing extent as the degree of long- range order increases [66Kre1, 66Kre2]. The magnetic structure of FePt3 is strongly related to temperature, composition, and degree of order [69Pal]. The TC of alloys with 79 to 92 at.% Pt is about -100 C [50Kus]. It is not clear to which phase the TC belongs. 07Isa: E. Isaac and G. Tammann, Z. Anorg. Allg. Chem., 55, 63-71 (1907) in German. 34Fal: M. Fallot, Compt. Rend., 199, 128-129 (1934) in French. 35Gra: L. Graf and A. Kussmann, Phys. Z., 36, 544-551 (1935) in German. 36Jel: W. Jellinghaus, Tech. Phys., 17(2), 33-36 (1936) in German. 38Fal: M. Fallot, Ann. Phys., 10, 291-332 (1938) in French. 38Mar: J. Martelly, Ann. Phys., 9, 318-323 (1938) in French. 41Lip: H. Lipson, D. Shoenberg, and G.V. Stupart, J. Inst. Met., 67, 333-340 ( 1941). 50Kus: A. Kussmann and G.G. v. Rittberg, Z. Metallkd., 42, 470-477 (1950) in German. 57Ber: A.E. Berkowitz, F.J. Donahoe, A.D. Franklin, and R.P. Steijn, Acta Metall., 5(1), 1-12 (1957). 58Cra: J. Crangle, Nature, 181, 644-645 (1958). 59Buc: R.A. Buckley and W. Hume-Rothery, J. Iron Steel Inst., (London), 193(1), 61-62 (1959). 62Cra: J. Crangle and J.A. Shaw, Philos. Mag., 7, 207-212 (1962). 63Bac1: G.E. Bacon and J. Crangle, Proc. R. Soc. (London) A, 272, 387-404 ( 1963). 63Bac2: G.E. Bacon and S.A. Wilson, Proc. Phys. Soc. (London), 82, 620-623 ( 1963). 63Sun: M. Sundaresen, Ya.I. Gerasimov, V.A. Geiderikh, and I.A. Vasil'eva, Zh. Fiz. Khim., 37(11), 2462-2466 (1963) in Russian; TR: Russ. J. Phys. Chem., 37( 11), 1330-1333 (1963). 65Kra: H.H. Kranzlein, M.S. Burton, and G.V. Smith, Trans. AIME, 233(1), 64-70 (1965). 65Kre: E. Kren and P. Szabo, Solid State Commun., 3(11), 371-372 (1965). 66Abr: E.P. Abrahamson II and S.L. Lopata, Trans. AIME, 236(1), 76-87 (1966). 66Kre1: E. Kren, P. Szabo, and T. Tarnoczi, Solid State Commun., 4(1), 31-32 ( 1966). 66Kre2: E. Kren, P. Szabo, and T. Tarnoczi, Acta Crystallogr., 21(7), Suppl., A97 (1966). 67Efs: E.J. Efsic and C.M. Wayman, Trans. AIME, 239(6), 873-882 (1967). 69Pal: D. Palaith, C.W. Kimball, R.S. Preston, and J. Crangle, Phys. Rev., 178( 2), 795-799 (1969). 73Dun: D.P. Dunne and C.M. Wayman, Metall. Trans., 4(1), 147-152 (1973). 73Miz: T. Mizoguchi, M. Akimitsu, and S. Chikazumi, J. Phys. Soc. Jpn., 34(4), 932-933 (1973). 73Zwe: L. Zwell, G.R. Speich, and W.C. Leslie, Metall. Trans., 4(8), 1990-1992 (1973). 74Mei: J.S. Meier, C.W. Christoe, and G. Wortmann, Solid State Commun., 15(3), 485-488 (1974). 74Men: A.Z. Men'shikov, Yu.A. Dorofeyev, V.A. Kazantsev, and S.K. Sidorov, Fiz. Met. Metalloved., 38(3), 505-518 (1974) in Russian; TR: Phys. Met. Metallogr., 38(3), 47-58 (1974). 75Men: A. Menshikov, T. Tarnoczi, and E. Kren, Phys. Status Solidi (a), 28, K85-K87 (1975). 75Tad: T. Tadaki and K. Shimizu, Scr. Metall., 9(7), 771-776 (1975). 76Cha: H. Chang, S. Hahn, and S. Sastri, Metall. Trans. A, 7(11), 1796-1798 ( 1976). 78Ski: D. Skinner and A.P. Miodownik, Platinum Met. Rev., 22(1), 21-24 (1978). 79Sum: K. Sumiyama, M. Shiga, M. Morioka, and Y. Nakamura, J. Phys. F, Met. Phys., 9(8), 1665-1667 (1979). 80Cha: H. Chang and S. Sastri, Metall. Trans. A, 11(1), 194-196 (1980). 81Mat: M. Matsui, K. Adachi, and H. Asano, Sci. Rep. Res. Inst. Tohoku Univ. A, 29(1), Suppl., 61-66 (1981). 82Swa: L.J. Swartzendruber, Bull. Alloy Phase Diagrams, 3(2), 161-165 (1982). Submitted to the APD Program. Complete evaluation contains 1 figure, 2 tables, and 63 references. 1