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Metallurgist

, Volume 61, Issue 11–12, pp 1115–1121 | Cite as

Preparation of Aluminum-Scandium Master Alloys by Aluminothermal Reduction of Scandium Fluoride Extracted from Sc2O3

  • B. P. Kulikov
  • V. N. Baranov
  • A. I. Bezrukikh
  • V. B. Deev
  • M. M. Motkov
Article
  • 35 Downloads

Aluminium alloys containing small additions of scandium exhibit unique operating properties. Alloying material with scandium significantly improves product weldability, reduces the tendency towards hot cracks and improves welded joint mechanical properties. The aim of this work is to increase the scandium extraction into a master alloy by preliminary transformation of scandium oxide into fluoride and introduction into the composition of an aluminium powder alloying additive. Results are provided of laboratory experiments for preparation of aluminium-scandium master alloy by aluminothermic reduction of scandium fluoride using sodium fluoride and aluminium powder within the alloy composition. Scandium fluoride is prepared by treating scandium oxide with 40% hydrofluoric acid. The overall extraction of scandium from oxide into fluoride and from fluoride to the aluminium-scandium master alloy is 88.5% with an average scandium concentration in the master alloy of 1.90 wt.%. The microstructure of the master alloy obtained is represented by scandium aluminide Al3Sc crystals with a size from 10 to 25 μm uniformly distributed within the master alloy. An additional reserve for increasing the extraction of scandium into the master alloy and reducing its cost is processing of slags formed in the preparation of the ligature. The use of an aluminium powder with high specific surface area in the composition of the alloying additive increases scandium extraction into the master alloy due to better contact of the reacting phases. The resultant Al–Sc master alloy has uniform distribution of Al3Sc particles within the volume of the metal.

Keywords

aluminium-scandium master alloy scandium oxide scandium fluoride aluminothermic reduction sodium fluoride scandium aluminide standard electrode potential 

References

  1. 1.
    S. P. Yatsenko, V. Diev, and B. Ovsyannikov, “New horizons for scandium,” Met. Evrazii, No. 4, 60–62 (2004).Google Scholar
  2. 2.
    V. V. Zakharov, “Effect of scandium on the structure and properties of aluminum alloys,” MiTOM, No. 7, 7–14 (2003).Google Scholar
  3. 3.
    V. I. Elagin, V. V. Zakharov, Yu. A. Filatov, et al., Patent 2081934 RF, IPC C22B21/06, “Wrought thermally unstrengthened alloy based on aluminum,” subm. 07.30.1995, publ. 06.20.2997, Byull., No. 17.Google Scholar
  4. 4.
    V. V. Zakharov, “Effect of scandium on the structure and properties of aluminum alloys,” MiTOM, No. 7, 7–15 (2003).Google Scholar
  5. 5.
    N. A. Belov and A. N. Alabin, “Prospective aluminum alloys with addition of zirconium and scandium,” Tsvet. Met., No. 2, 99–106 (2007).Google Scholar
  6. 6.
    I. N. Pyagai, S. P. Yatsenko, and V. N. Skachkov, “Pilot plant production for extracting scandium from aluminum production slurry,” Tsvet. Met., No. 12, 75–79 (2011).Google Scholar
  7. 7.
    A. Yu. Nikolaev, A. V. Sudal’tsev, and Yu. P. Zaikov, “Electro-separation of scandium and aluminum from molten NaF–AlF3–ScF3,” Proc. 7th Int. Congr. Nonferrous Metals and Minerals, Krasnoyarsk (2016), pp. 112–113.Google Scholar
  8. 8.
    S. P. Yatsenko, N. A. Khokhlova, L. A. Pasechnik, and N. A. Sabirzyanov, “Preparation of master alloy based on aluminum by high-temperature bulk reaction in molten slats. Multicomponent modification of aluminum master alloy with scandium, zirconium, and hafnium,” Rasplavy, No. 2, 89–94 (2010).Google Scholar
  9. 9.
    S. V. Aleksandrovskii V. M. Sizyakov, E. A. Brylevskaya, et al., Patent 2261924 RF, IPC C22B5/04, “Method for preparing scandium-containing master alloy,” subm. 05.26.2004, publ. 10.10.2005, Byull., No. 28.Google Scholar
  10. 10.
    S. V. Aleksandrovskii and V. M. Sizyakov, Patent 2162112 RF, IPC C22C21/04, “Method for preparing scandium-containing master alloy,” subm. 07.19.1999, publ. 01.20.2001, Byull., No. 2.Google Scholar
  11. 11.
    V. Yu. Bazhin, Y. I. Kosov, O. L. Lobacheva, and N. V. Dzhevaga, “Synthesis of aluminum-based scandium–yttrium master alloys,” Russ. Metallurgy (Metally), 2015, No. 7, 516–520 (2015).CrossRefGoogle Scholar
  12. 12.
    V. Yu. Bazhin, S. A. Savchenkov, and E. M. Gutema, “Production technology features for aluminum matrix alloys with a silicon carbide framework,” Metallurgist, 60, No. 11–12, 1267–1272 (2017).Google Scholar
  13. 13.
    S. V. Makhov and V. I. Moskvitin, Patent 2213795 RF, IPC C22C1/00, “Method for preparing aluminum-scandium master alloy (versions),” subm. 11.12.2001, publ. 10.10.2003, Byull., No. 28.Google Scholar
  14. 14.
    A. B. Shubin, and K. Yu. Shunyaev, Patent 2507291 RF, IPC C22C21/00, “Method for preparing aluminum-scandium master alloy,” subm. 02.11.2013, publ. 0.2.20.2014, Byull., No. 5.Google Scholar
  15. 15.
    B. P. Kuliov, V. E. Zheleznyak, and V. E. Lisai, Patent 2092594 RF, IPC C22B9/10, “Alloying additive,” subm. 11.23.1992, publ. 10.10.1997, Byull., No. 29.Google Scholar
  16. 16.
    V. I. Napalkov and S. V. Makhov, Alloying and Modification of Aluminum and Magnesium, MISiS, Moscow (2002).Google Scholar

Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  • B. P. Kulikov
    • 1
  • V. N. Baranov
    • 1
  • A. I. Bezrukikh
    • 1
  • V. B. Deev
    • 2
  • M. M. Motkov
    • 1
  1. 1.Siberian Federal UniversityKrasnoyarskRussia
  2. 2.National University of Science and Technology MISiSMoscowRussia

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