Institute of High-Temperature Electrochemistry (Ural Branch RAS), Ekaterinburg, Russia:
A. V. Suzdaltsev, Senior Researcher of Electrolysis Department, e-mail: suzdaltsev_av@mail.ru

Yu. P. Zaikov, Researcher of Electrolysis Department

Ural Federal University, Ekaterinburg, Russia:

A. Yu. Nikolaev, Senior Lecturer

Recent years showed the increased urgency of developing new resource- and energy-saving methods for obtaining alloys, master alloys and composite materials based on aluminum and other metals. In particular, our article is a brief review of the main scientific and technological features of modern methods for obtaining Al – Sc master alloys. The main producers of Al – Sc master alloys in Russia and abroad are listed. Our scientific and technical information defined three main ways for producing Al – Sc master alloys:
– direct alloying of scandium with aluminum;
– aluminothermic synthesis using scandium salts or oxide as a scandium source;
– electrowinning from molten salts using scandium salts or oxide as a scandium source.
The essence of listed methods is briefly described in this article. The views of different authors on the mechanisms are given (in particular, the aluminothermic reduction of scandium salts). Advantages and disadvantages were analyzed and gave a comparative evaluation of parameters of the most promising methods for further development. As parameters, data on the process temperature, scandium content in obtained master alloys was analyzed together with the degree of scandium extraction from its sources. In conclusion, we describe the results of recent studies of Institute of High-Temperature Electrochemistry for developing an energy-effective and resourcesaving method for the continuous production of Al – Sc master alloys by electrolysis of oxide-fluoride melts with scandium oxide. A high competitiveness of electrolysis of oxide-fluoride KF – NaF – AlF₃ – Al₂O₃ – Sc₂O₃ melts for production of Al – Sc master alloys of 2 wt. % of scandium was shown.

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