Ural Federal University, Ekaterinburg, Russia:

A. A. Filatov, Engineer, Post-Graduate Student

A. Yu. Nikolaev, Junior Researcher, Senior Lecturer

Institute of High-Temperature Electrochemistry of the Ural Branch of the Russian Academy of Sciences, Ekaterinburg, Russia:
P. S. Pershin, Researcher
A. V. Suzdaltsev, Senior Researcher, Candidate of Chemical Sciences, e-mail: suzdaltsev_av@mail.ru

We investigated the influence of ZrO₂ content (0.25–1.50% (wt.) ), aluminium stirring, duration of aluminium-thermal synthesis (from 15 to 180 min) and electrolysis on the content and extraction of zirconium from its oxide into aluminium in a light-melting molten mixtures KF – AlF₃, NaF – AlF₃ and KF – NaF – AlF₃ in the temperature range of 750–800 ^оС. Increasing of zirconium extraction into aluminium is the most contribute to the stirring of the aluminium, increasing the fraction of KF in the KF – NaF – AlF₃ melt and also carrying out the electrolysis of melts at the cathode current density of 0.5 A/cm². The resulting alloys and master-alloys of Al – Zr with zirconium content up to 1.1% (wt.) with the extraction of zirconium 94–96% were synthesized via the aluminium-thermal method. Based on the obtained results, parameters of the electrolysis of KF – AlF3, NaF – AlF₃ and KF – NaF – AlF₃ melts with the addition of ZrO₂ were chosen. Electrolysis tests showed the principal possibility of Al – Zr alloys obtaining with the Zr concentration up to 15% (wt.) with the extraction of zirconium from its oxide 95% and higher. Structural features of obtained Al – Zr alloys were investigated using the scanning electron microscopy and Х-ray phase analysis. The most part of the zirconium in the Al – Zr alloy (with 15% (wt.) of Zr) is presented in the form of phases of inter-metallic compounds of Al₃Zr with the size of 5 to 50 microns.

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