Lab Scale Synthesis of Al-Sc Alloys in NaF-AlF₃-Al₂O₃-Sc₂O₃ Melt

Abstract

The liquidus temperature in the [NaF-AlF3(30 mol.%)]-Sc2O3 molten system with the Sc2O3 additions up to 12 wt% was measured by the thermo analysis. The effect of the cathode current density (0, 0.25, 0.50, and 1.0 A∙cm-2), the Sc2O3 content (1, 2, 4, and 8 wt%) in the NaF-AlF3(30 mol.%)-Al2O3-Sc2O3 electrolyte, the rate of the molten aluminum agitation (0, 100 rotates/min), the synthesis duration (30-210 min) on the Sc content in the aluminum alloy at 980 °С was studied. The Al-Sc alloys with the scandium content of 0.15-1.30 wt%, depending on the synthesis conditions, and with the uniform Sc distribution throughout the aluminum matrix were produced.

Review—Synthesis of Aluminum Master Alloys in Oxide-Fluoride Melts: A Review

“…31 Synthesis of Al-Sc master alloys.-Electrolysis tests for the production of Al-Sc master alloys using a liquid aluminum cathode were carried out in a wide range of oxide-fluoride melts and synthesis conditions. 24,25,91 Alloys and master alloys of Al-Sc with scandium content not higher than 1.2 wt% were obtained under the conditions of aluminum-thermal synthesis. Depending on the parameters of the synthesis, the recovery of scandium from its oxide ranged from 20 to 75%, while the maximum extraction was achieved in KF-AlF 3 -based melts even at a relatively low temperature (Fig.…”