Vyatka State University, Kirov, Russia:

D. A. Kondratev, Assistant Professor of a Chair “Electrochemical production technologies”, e-mail: denis512a@mail.ru
+A. V. Kovalevskiy

The influence of temperature and process duration on the specific mass changes of nickel and cobalt samples (P = Δm/S, where m — mass change of the sample, S — surface area of the sample) was studied using the gravimetric method, when their diffusion saturation with neodymium was carried out with the absence of electric current in molten eutectic mixture of lithium and potassium chlorides with 5 %(wt.) of neodymium chloride. Dehydrated lithium, potassium and neodymium chlorides (KhCh (ХЧ), neodymium NM-1 (НМ-1), nickel NP-2 (НП-2) and cobalt K-1) were used for the experiment. The crucible, made of beryllium oxide, fixed in a closed quartz test-tube was used as a container for eutectic mixture. The process was carried out in the purified argon. The fasteners for specimens were made of molybdenum wire. According to the experimental results, there were calculated the mathematical relationships of P from the duration of the process for nickel samples in the temperature range of 773–973 K (τ = 1–8 h) and cobalt samples in the temperature range of 773–873 K (τ = 1–6 h). Analysis of the dependencies has shown that the rate-limiting step of the process transference neodymium without electric current to nickel and cobalt samples, is the diffusion in the solid phase. Composition of alloys-coatings, obtained with current-free transfer of neodymium to nickel and cobalt, was studied using X-ray fluorescence spectrometer, X-ray microprobe and scanning microscope. On the basis of this analysis, there was made a definition that, the coatings, forming under the experimental conditions on metal substrate surface consist of one structural zone — intermetallic compound NdNi₂(NdCo₂).

1. Kuznetsov S. A. Sbornik XIV Vserossiyskoy konferentsii po fizicheskoy khimii i elektrokhimii ionnykh rasplavov i tverdykh elektrolitov. Tom 1 (Bulletin of the XIV All-Russian conference on physical chemistry and electrochemistry of ionic melts and solid electrolytes. Volume 1). Ekaterinburg : Institute of High-Temperature Electrochemistry of Ural Branch оf Russian Academy of Sciences, 2007. p. 110.
2. Verbetskiy V. N., Velikorodnyy Yu. A., Lushchekina S. V. Sintez gidrida na osnove intermetallicheskogo soedineniya YbN (Hybrid synthesis based on intermetallic compound YbN). Vestnik Moskovskogo universiteta. Seriya 2. Khimiya = Bulletin of Moscow University. Series 2. Chemistry. 2002. Vol. 43, No. 1. pp. 58–60.
3. Azhazha V. M., Borts B. V., Vanzha A. F., Rybalchenko N. D., Shevyakova E. P. Vozmozhnosti primeneniya redkozemelnykh elementov pri sozdanii konstruktsionnykh materialov dlya atomnoy promyshlennosti Ukrainy (Possibilities of application of rare-earth elements during the creation of construction materials for atomic industry of Ukraine). Voprosy atomnoy nauki i tekhniki = Problems of Atomic Science and Technology. 2008. No. 1. pp. 195–201.
4. Kushkhov Kh. B., Vindizheva M. K., Mukozheva R. A., Tlenkopachev M. R., Abazova A. Kh. Elektrovosstanovlenie ionov tseriya (III) na serebryanom elektrode v khloridnom rasplave pri 823 K (Electroreduction of cerium (III) ions on silver electrode in chloride melt at the temperature of 823 K). Elektrokhimiya = Russian Journal of Electrochemistry. 2013. Vol. 49, No. 4. pp. 411–415.
5. Kushkhov Kh. B., Vindizheva M. K., Mukozheva R. A., Tlenkopachev M. R., Nafonova M. N. Issledovanie elektrovosstanovleniya ionov lantana na volframovom elektrode v galogenidnykh rasplavakh pri T = 823 K (Investigation of electroreduction of lanthane ions on tungsten electrode in halogenide melts at the temperature of 823 K). Rasplavy = Russian Metallurgy (Metally). 2012. No. 1. pp. 50–59.
6. Novoselova A. V., Smolenskii V. V. Electrochemical and thermodymamic properties of lanthanides (Nd, Sm, Eu, Tm, Yb) in alkali metal chloride melts. Radiochemistry. 2013. Vol. 55, No. 3. pp. 243–256.
7. Novoselova A. V., Smolenskii V. V. Electrochemical study of the reduction of Tm (III) ions in a molten NaCl – 2CsCl eutectic. Russian Journal of Applied Chemistry. 2012. Vol. 85, No. 2. pp. 229–235.
8. Ilyushchenko N. G., Anfinogenov A. I., Shurov N. I. Vzaimodeystvie metallov v ionnykh rasplavakh (Interaction of metals in ionic melts). Moscow : Nauka, 1991. 176 p.
9. Kovalevskiy A. V., Kondratev D. A., Chebykin V. V. Reaktsionnaya emkost i elektrokhimicheskie svoystva rasplava LiCl – KCl, vyderzhannogo v kontakte s disproziem i neodimom (Reaction capacity and electrochemical properties of the alloy LiCl – KCl, in the contact with dysprosium and neodymium). Rasplavy = Russian Metallurgy (Metally). 2013. No. 2. pp. 77–82.
10. Novoselova A. V., Smolenskiy V. V. Elektrokhimicheskoe issledovanie svoystv ionov Nd (III) i Nd (II) v rasplavlennoy evtektike LiCl – KCl – CsCl i individualnom CsCl (Electrochemical investigation of the properties of Nd (III) and Nd (II) in molten eutectics of LiCl – KCl – CsCl and individual CsCl). Elektrokhimiya = Russian Journal of Electrochemistry. 2013. Vol. 49, No. 10. pp. 1041–1047.
11. Kushkhov Kh. B., Chuksin S. I., Zhanikaeva Z. A. Elektrovosstanovlenie ionov neodima i prazeodima v ekvimolnom KCl – NaCl – CsCl rasplavakh na volframovom elektrode (Electroreduction of neodymium and praseodymium ions in equimolar KСl – NaCl – CsCl melts on tungsten electrode). Rasplavy = Russian Metallurgy (Metally). 2013. No. 3. pp. 87–96.
12. Uehara A., Fukasawa K., Nagai T., Fujii T., Yamana H. Separation of Nd metal by using disproportionation reaction of Nd (II) in molten chlorides. Journal of Nuclear Materials. 2011. No. 414. pp. 336–339.
13. Fukasawa K., Ueharab A., Nagaic T., Fujii T., Yamana H. Journal of Alloys and Compounds. 2011. No. 509. pp. 5112–5118.
14. Potapov A. M., Khokhlov V. A., Sato Y. Pogloshchenie vlagi iz vozdukha khloridami redkozemelnykh metallov (Moisture pick-up from the air by rareearth metal chlorides). Sbornik XIII Rossiyskoy konferentsii po fizicheskoy khimii i elektrokhimii rasplavlennykh i tverdykh elektrolitov. Tom I (Collection of the XIII Russian conference on physical chemistry and electrochemistry of molten and solid electrolytes. Volume I). Ekaterinburg : Institute of High-Temperature Electrochemistry of Ural Branch of Russian Academy of Sciences, 2004. pp. 220–222.
15. Baraboshkin A. N. Ob usloviyakh polucheniya gladkikh diffuzionnykh pokrytiy bestokovym perenosom i elektroosazhdeniem (About the conditions of obtaining of smooth diffusion coverings by currentless transfer and electrosedimentation). Vysokotemperaturnaya elektrokhimiya: kinetika : sbornik statey (High-temperature electrochemistry: kinetics : collection of articles). Sverdlovsk : Ural Science Center of USSR Academy of Sciences, 1986. pp. 36–41.
16. Gshneyder K. A. Splavy redkozemelnykh metallov (Rare-earth metal alloys). Moscow : Mir, 1965. 427 p.
17. Elkin O. V., Chebykin V. V., Kovalevskiy A. V. Kinetika splavoobrazovaniya pri bestokovom perenose itterbiya, samariya i gadoliniya na nikel v khloridnykh rasplavakh (Kinetics of alloy-formation during the currentless transfer of ytterbium, samarium and gadolinium on nickel in chloride melts). Rasplavy = Russian Metallurgy (Metally). 2009. No. 4. pp. 20–26.
18. Kovalevskiy A. V., Soroka V. V. Diffuzionnoe nasyshchenie kobalta redkozemelnymi metallami v khloridnykh rasplavakh (Diffusion saturation of cobalt by rare-earth metals in chloride melts). Sbornik nauchnoprakticheskoy konferentsii “Sovershenstvovanie tekhnologii galvanicheskikh pokrytiy” (Collection of scientific-practical conference “Improvement of the technology of galvanic coatings”). Kirov : Kirov Polytechnic University, 1986. pp. 39–40.
19. Diagrammy sostoyaniya dvoynykh metallicheskikh sistem : spravochnik (State diagrams of double metallic systems : reference book). Under the editorship of N. P. Lyakishev. Moscow : Mashinostroenie, 2001. 872 p.
20. Voroshnin L. G., Khusid B. M., Khina B. Kh. Issledovanie i razrabotka teoreticheskikh problem v oblasti poroshkovoy metallurgii i zashchitnykh pokrytiy : sbornik statey. Chast 3 (Investigation and development of theoretical problems in the area of powder metallurgy and protection coatings : collection of articles. Part 3). Minsk : BelNIINTI, 1984. pp. 44–51.