Synthesis of Silumins in KF-AlF3-SiO2Melts

The possibility of obtaining silumins in KF-AlF 3 melts via SiO 2 additions at a temperature of 720°C is investigated. Silumins with high silicon contents (up to 37 wt%) can be obtained in KF-AlF 3 -SiO 2 melts via the electrochemical co-deposition of aluminum and silicon on a graphite cathode in both galvanostatic and potentiostatic modes. Electrode processes are studied with cyclic voltammetry. It is shown that the peak of silicon cathode deposition with the addition of SiO 2 is fixed at a potential of about −0.8 V (in relation to the CO/CO 2 reference electrode). The expansion of the silicon allocation potential area from a value of −0.5 V with increasing concentration of SiO 2 in the melt indicates the complex ionic structure of the melt.