Abstract
The composition and crystal structure of compounds produced by self-propagating high-temperature synthesis (SHS) from the 5Ta–2Ni–3Al (at %) powder mixture followed by vacuum remelting at 3000°C are studied. The SHS product contains the following phases: TaNiAl (Laves τ1 phase), NiAl, Ni2Al3, and Ta. Its microstructure includes Ta85Ni7Al8, Ta52Ni20Al28, and Ta53Ni25Al22 ternary phases according to elemental analysis data. Reflections belonging to no known ternary phases in the Ta–Ni–Al system under consideration are revealed in the X-ray diffraction pattern of the remelted material. Based on the homological approach, it is found that these reflections belong to three phases with the structural types W6Fe7 (\(R\bar {3}m\)), Ti2Ni (\(Fd\bar {3}m\)), and Ta3Al (\({{P{{4}_{2}}} \mathord{\left/ {\vphantom {{P{{4}_{2}}} {mnm}}} \right. \kern-0em} {mnm}}\)). They are identified as reflections of three compounds, Ta6.5Ni6.5, Ti2Ni, and Ta2.84Al0.91, with unit-cell parameters differing from these for the same compounds with the conservation of the structural type. An increase in the unit-cell parameters of all revealed phases is noted when compared with known binary intermetallic compounds. This can be associated with the presence of Al atoms in the crystal lattice from the Ta6.5Ni6.5 phase and Al and Ta atoms in the phase with the Ti2Ni structural type. Phases Ta6.5Ni6.5 and Ti2Ni phases are identified as Ta6Ni6Al and Ta2Ni0.5Al0.5 by X-ray structural analysis and crystal-chemical modeling, and their structural type, composition, and unit-cell parameters are determined. The structure and composition are refined by the full-profile analysis, and the unit-cell parameters of the phases and their quantitative ratio in the material are determined. The phase composition of the material is as follows, wt %: 47 Ta6Ni6Al, 16 Ta2Ni0.5Al0.5, and 37 Ta3Al.
Similar content being viewed by others
REFERENCES
Raghavan, V., Al–Ni–Ta (aluminum–nickel–tantalum), J. Phase Equilib. Diffus., 2006, vol. 27, no. 4, pp. 405–407. https://doi.org/10.1007/s11669-006-0016-0
da Rocha, F.S., Fraga, G.L.F., Brandão, D.E., Da Silva, C.M., and Gomes, A.A., Specific heat and electronic structure of Heusler compounds Ni2TAl (T = Ti, Zr, Hf, V, Nb, Ta), Phys. B (Amsterdam, Neth.), 1999, vol. 269, no. 2, pp. 154–162. https://doi.org/10.1016/S0921-4526(99)00102-7
Zhou, S., Chen, L.Q., MacKay, R.A., and Liu, Z.K. Evaluation of the thermodynamic properties and phase equilibria of the ordered γ' and disordered γ phases in the Ni-Al-Ta system, MRS Proc., 2002, vol. 755, pp. 443–450. https://doi.org/10.1557/PROC-755-DD11.25
Subramanian, P.R., Miracle, D.B., and Mazdiyasni, S., Phase relationships in the Al–Ta system, Metall. Trans. A, 1990, vol. 21, no. 2, pp. 539–545. https://doi.org/10.1007/BF02671926
Miura, S., Hong, Y.M., Suzuki, T., and Mishima, Y., Liquidus and solidus temperatures of Ni-solid solution in Ni–Al–X (X: V, Nb and Ta) ternary systems, J. Phase Equilib. Diffus., 2001, vol. 22, no. 3, pp. 345–351. https://doi.org/10.1361/105497101770338860
Johnson, D.R. and Oliver, B.F., Ternary peritectic solidification in the NiAl–Ni2AlTa–NiAlTa system, Mater. Lett., 1994, vol. 20, nos. 3–4, pp. 129–133. https://doi.org/10.1016/0167-577X(94)90074-4
Zakharov, A., Aluminium-nickel-tantalum, in Ternary Alloys: A Comprehensive Compendium of Evaluated Constitutional Data and Phase Diagrams: Al–Mg–Se to Al–Ni–Ta, New York: Wiley-VCH, 1992, vol. 7, pp. 483–497.
Villars, P., Prince, A., and Okamoto, H., Al–Ni–Ta. Handbook of Ternary Alloy Phase Diagrams, Materials Park, OH: ASM Int., 1995, vol. 4, pp. 4186–4192.
Kuznetsov, V., Al–Ni–Ta (aluminium–nickel–tantalum), in Light Metal Systems, part 3 of Landolt-Börnstein—Group IV Physical Chemistry, Berlin, Heidelberg: Springer, 2005, vol. 11A3, pp. 425–439. https://doi.org/10.1007/10915998_33
Palm, M., Sanders, W., and Sauthoff, G., Phase equilibria in the Ni–Al–Ta system, Z. Metallkd., 1996, vol. 87, no. 5, pp. 390–398.
Shchukin, A.S. Vrel, D., and Sytschev A.E, Interaction of NiAl intermetallic during SHS synthesis with Ta substrate, Adv. Eng. Mater., 2018, vol. 20, no. 8, p. 1701077. https://doi.org/10.1002/adem.20170107
Shchukin, A.S., Kovalev, D.Yu., Sytschev, A.E., and Shcherbakov, A.V., Formation of new intermetallic phases in the Ta–Ni–Al system, Perspekt. Mater., 2019, no. 10, pp. 5–13. https://doi.org/10.30791/1028-978X-2019-10-5-13
Macrae, C.F., Bruno, I.J., Chisholm, J.A., Edgington, P.R., McCabe, P., Pidcock, E., Rodriguez-Monge, L., Taylor, R., van de Streek, J., and Wood, P.A., Mercury CSD 2.0—New features for the visualization and investigation of crystal structures, J. Appl. Crystallogr., 2008, vol. 41, no. 2, pp. 466–470. https://doi.org/10.1107/S0021889807067908
Zeumert, B. and Sauthoff, G., Intermetallic NiAl–Ta alloys with strengthening Laves phase for high-temperature applications, I. Basic properties, Intermetallics, 1997, vol. 5, no. 7, pp. 563–577. https://doi.org/10.1016/S0966-9795(97)00031-9
Kripyakevich, P.I., Gladyshevskii, E.I., and Pylaeva, E.N., W6Fe7 compounds in Ta–Ni and Nb–Ni systems, Kristallografiya, 1962, vol. 7, no. 2, pp. 212–216
Yurko, G.A., Barton, J.W., and Parr, J.G., The crystal structure Ti2Ni, Acta Crystallogr., 1959, vol. 12, no. 11, pp. 909–911. https://doi.org/10.1107/S0365110X59002559
Edshammar, Lars-Erik and Holmberg, B., The σ-phase Ta2Al, Acta Chem. Scand., 1960, vol. 14, no. 5, pp. 1219–1220. https://doi.org/10.3891/acta.chem.scand.14-1219
Boulineau, A., Joubert, J.M., and Cerny, R., Structural characterization of the Ta-rich part of the Ta–Al system, J. Solid State Chem., 2006, vol. 179, no. 11, pp. 3385–3393. https://doi.org/10.1016/j.jssc.2006.07.001
Batsanov, S.S., Strukturnaya khimiya. Fakty i zavisimosti (Structural Chemistry. Facts and Dependencies), Moscow: Dialog-MGU, 2000.
Novotny, H., Bruki, C., and Benesovsky, F., Untersuchungen in den systemen tantal–aluminium–silicium und wolfram–aluminium–silicium, Monatsh. Chem., 1961, vol. 92, no. 1, pp. 116–127.
Bilic, A., Gale, J.D., Gibson, M.A., Wilson, N., and McGregor, K., Prediction of novel alloy phases of Al with Sc or Ta, Sci. Rep., 2015, vol. 5, p. 9909. https://doi.org/10.1038/step9909
McCusker, L.B., Von Dreele, R.B., Cox, D.E., Louër, D., and Scardi, P., Rietveld refinement guidelines, J. Appl. Crystallogr., 1999, vol. 32, no. 1, pp. 36–50. https://doi.org/10.1107/S0021889898009856
Author information
Authors and Affiliations
Corresponding authors
Ethics declarations
The authors declare that they have no conflict of interest.
Additional information
Translated by N. Korovin
About this article
Cite this article
Shchukin, A.S., Konovalikhin, S.V., Kovalev, D.Y. et al. Composition and Crystalline Structure of Ternary Phases in the Ta–Ni–Al System. Russ. J. Non-ferrous Metals 61, 303–308 (2020). https://doi.org/10.3103/S1067821220030141
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.3103/S1067821220030141