Abstract
The Nd-Au phase diagram was studied in the 0 to 100 at. pct Au composition range by differential thermal analysis (DTA), X-ray diffraction (XRD), optical microscopy (LOM), scanning electron microscopy (SEM), and electron probe microanalysis (EPMA). Six intermetallic phases were identified, the crystallographic structures were determined or confirmed, and the melting behavior was determined, as follows: Nd2Au, orthorhombic oP12-Co2Si type, peritectic decomposition at 810 °C; NdAu, R.T. form, orthorhombic oP8-FeB type, H.T. forms, orthorhombic oC8-CrB type and, at a higher temperature, cubic cP2-CsCl type, melting point 1470 °C; Nd3Au4, trigonal hR42-Pu3Pd4 type, peritectic decomposition at 1250 °C; Nd17Au36, tetragonal tP106-Nd17Au36 type, melting point 1170 °C; Nd14Au51, hexagonal hP65-Gd14Ag51 type, melting point 1210 °C; and NdAu6, monoclinic mC28-PrAu6 type, peritectic decomposition at 875 °C. Four eutectic reactions were found, respectively, at 19.0 at. pct Au and 655 °C, at 63.0 at. pct Au and 1080 °C, at 72.0 at. pct Au and 1050 °C, and, finally, at 91.0 at. pct Au and 795 °C. A catatectic decomposition of the (βNd) phase, at 825 °C and ≈1 at. pct Au, was also found. The results are briefly discussed and compared to those for the other rare earth-gold (R-Au) systems. A short discussion of the general alloying behavior of the “coinage metals” (Cu, Ag, and Au) with the rare-earth metals is finally presented.
Similar content being viewed by others
References
A. Palenzona and P. Manfrinetti: J. Alloys Compounds, 1997, vol. 257, pp. 224–26.
A. Saccone, S. Delfino, D. Macciò, and R. Ferro: J. Chimie Phys. Phys.-Chimie Biol., 1997, vol. 94, pp. 948–57.
G. Canneri: Metall. Ital., 1931, vol. 23, p. 803.
O. D. McMasters, K.A. Gschneidner, Jr., G. Bruzzone, and A. Palenzona: J. Less-Common Met., 1971, vol. 25, pp. 135–60.
L. Rolla, A. Iandelli, G. Canneri, and R. Vogel: Z. Metallkd., 1943, vol. 35, pp. 29–42.
A. Saccone, D. Macciò, M. Giovannini, and S. Delfino: J. Alloys Compounds, 1997, vol. 247, pp. 134–40.
A. Borsese, R. Capelli, S. Delfino, and R. Ferro: Accad. Naz. Lincei—Rend. Classe Sci. Fis. Mater., Serie VIII, 1973, vol. 54, pp. 957–60.
A. Saccone, D. Macciò, S. Delfino, and R. Ferro: Proc. 6th Eur. Symp. on Thermal Analysis and Calorimetry (ESTAC 6), University of Trieste Publ., Trieste, Italy, 1994, Grado, Italy, 11–16, Sept. 1994, p. 267
O.D. McMasters and K.A. Gschneidner, Jr.: J. Less-Common Met., 1973, vol. 30, pp. 325–42.
A. Saccone, M.L. Fornasini, D. Macciò, and S. Delfino: Intermetallics, 1996, vol. 4, pp. 111–19.
A. Palenzona: J. Less-Common Met., 1984, vol. 100, pp. 135–40.
A. Iandelli and A. Palenzona: J. Less-Common Met., 1969, vol. 18, pp. 221–27.
P.E. Rider, K.A. Gschneidner, Jr., and O.D. McMasters: Trans. Metall. AIME, 1965, vol. 233, pp. 1488–96.
P. Villars and L.D. Calvert: Pearson’s Handbook of Crystallographic Data, 2nd ed., ASM INTERNATIONAL, Materials Park, OH, 1990.
C.C. Chao, H.L. Luo, and P. Duwez, Jr.: J. Appl. Phys., 1963, vol. 34, pp. 1971–73.
M.L. Fornasini and A. Saccone: Z. Kristallogr., 1994, vol. 209, pp. 657–59.
C. Donolato and S. Steeb: J. Less-Common Met., 1969, vol. 18, pp. 312–13.
J.M. Moreau and E. Parthé: Acta Crystallogr., 1974, vol. B30, pp. 1743–48.
K.A. Gschneidner, Jr., F.W. Calderwood, H. Okamoto, and T.B. Massalski: in Phase Diagrams of Binary Gold Alloys, H. Okamoto and T.B. Massalski, eds., ASM INTERNATIONAL, Metals Park, OH, 1987, pp. 191–93.
A. Saccone, A.M. Cardinale, S. Delfino, and R. Ferro: Z. Metallkd., 1996, vol. 87, pp. 82–87.
Binary Alloy Phase Diagrams, 2nd ed, T.B. Massalski, ASM INTERNATIONAL, Materials Park, OH, 1990.
K.A. Gschneidner, Jr.: Bull. Alloy Phase Diagrams, 1990, vol. 11, pp. 216–24.
P. Villars, A. Prince, and H. Okamoto: Handbook of Ternary Alloy Phase Diagrams, ASM INTERNATIONAL, 1995, vol. 1.
R. Ferro, A. Saccone, S. Delfino, A.M. Cardinale, and D. Macciò: Metall. Mater. Trans. B, 1996, vol. 27B, pp. 979–86.
J. Flahaut and F. Thévet: J. Solid State Chem., 1980, vol. 32, pp. 365–76.
G.V. Raynor: J. Less-Common Met., 1972, vol. 29, pp. 333–36.
C. Colinet and A. Pasturel: in Handbook on the Physics and Chemistry of Rare Earths, K.A. Gschneidner, Jr. L. Eyring, G.H. Lander, and G.R. Choppin, eds., Elsevier, Amsterdam, 1994, vol. 19, pp. 479–647.
F.R. de Boer, R. Boom, W.C.M. Mattens, A.R. Miedema, and A.K. Niessen: in Cohesion in Metals. Transition Metal Alloys, F.R. de Boer and D.G Pettifor, eds., North Holland, Amsterdam, 1988, vol. 1.
K.A. Gschneidner, Jr.: J. Less.-Common Met., 1969, vol. 17, pp. 1–12.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Saccone, A., Macciò, D., Delfino, S. et al. The neodymium-gold phase diagram. Metall Mater Trans A 30, 1169–1176 (1999). https://doi.org/10.1007/s11661-999-0266-7
Received:
Issue Date:
DOI: https://doi.org/10.1007/s11661-999-0266-7