Фазовая диаграмма системы Fe-Hf

К оглавлению: Другие диаграммы (Others phase diargams)

Fe-Hf (Iron-Hafnium) H. Okamoto Reports on the Fe-Hf phase diagram are significantly conflicting. Because some of the problems are probably due to difficulty in obtaining high-purity Hf in earlier works, the assessed Fe-Hf phase diagram is based on relatively recent investigations by [61Sve] and [73Koc]. Three closely related intermediate phases (MgZn2-, MgNi2-, and CuMg2-type) exist near the composition of Fe2Hf. The phase relationships among them are uncertain. They are identified tentatively as l, bFe2Hf, and aFe2Hf, respectively, here. The only other intermediate phase in this system is FeHf2. All of the assessed phase boundaries are considered to be tentative, although they are shown with solid lines. The most recent values for the Fe-rich eutectic temperature, 1390 C [ 73Koc], and the eutectic composition, 7.9 at.% Hf [61Sve], are accepted in the assessed diagram. The solubility of Hf in (aFe) is 0.18, 0.1, 0.06, and 0.04 at.% at 900, 800, 700, and 600 C, respectively [66Abr]. In reasonable agreement, the solubility is <0.1 at.% Hf [60Rei] or 0.06 at.% Hf at the peritectoid temperature [61Sve]. The reported Hf-rich eutectic temperatures are in reasonable agreement: 1280 [ 56Hay], 1300 с 10 [61Sve], or 1300 C [73Koc]. The accepted eutectic composition is 63.9 at.% Hf [61Sve]. The Curie temperatures of l (at 33.3 at.% Hf) and aFe2Hf are 154 and 315 C, respectively [77Ike]. According to [61Sve], the Curie temperature of "Fe2Hf" is 370 C on the Fe-rich end and 200 C on the Hf-rich end of the homogeneity range. Because the phase relationships were not well established, the Curie temperatures of these phases are uncertain. 54Ell: R.P. Elliott, Tech. Rep. 1, OSR Tech. Note OSR-TN-54-247, Armour Research Foundation, Chicago, IL, 11 p (1954). 56Hay: E.T. Hayes and D.K. Deardorff, USAEC (Zirconium Progress Report) USBM-U- 158, 22 p (1956); as quoted in [60Tho]. 58Ell: R.P. Elliott, Trans. ASM, 50, 617-633 (1958). 59Woo: E.A. Wood, Z. Krist., 112, 97 (1959). 60Nev: M.V. Nevitt, J.W. Downey, and R.A. Morris, Trans. AIME, 218(12), 1019- 1023 (1960). 60Rei: R. Reinbach, Z. Metallkd., 51(5), 292-294 (1960) in German. 60Tho: D.E. Thomas and E.T. Hayes, The Metallurgy of Hafnium, USAEC, 202 (1960) . 61Ell: R.P. Elliott, Trans. ASM, 53, 321-329 (1961). 61Sve: V.N. Svechnikov and A.K. Shurin, Dokl. Akad. Nauk SSSR, 139(4), 895-898 (1961) in Russian; TR: Proc. Acad. Sci. USSR, Chem. Sect., 139(4), 774-777 ( 1961). 64Kri: P.I. Kripyakevich, M.A. Tylkina, and I.A. Tsyganova, Zh. Neorg. Khim., 9(11), 2599-2601 (1964) in Russian; TR: Russ. J. Inorg. Chem., 9(11), 1404- 1405 (1964). 66Abr: E.P. Abrahamson II and S.L. Lopata, Trans. AIME, 236(1), 76-87 (1966). 73Koc: Yu.A. Kocherzhinskiy, V.Ya. Markiv, and V.V. Pet›kov, Izv. Akad. Nauk SSSR, (1), 189-195 (1973) in Russian; TR: Russ. Metall., (1), 134-140 (1973). 77Ike: K. Ikeda, Z. Metallkd., 68(3), 195-198 (1977). 79Ess: R.M. van Essen and K.H.J. Buschow, J. Less-Common Met., 64(2), 277-284 ( 1979). 86Kra: A.M. van der Kraan, Physica B, 138, 55-62 (1986). Submitted to the APD Program. Complete evaluation contains 1 figure, 2 tables, and 20 references. 1