The Electrochemical Co-reduction of Mg-Al-Y Alloys in the LiCl-NaCl-MgCl2-AlF3-YCl3 Melts

• Published in: Metallurgical and materials transactions. B, Process metallurgy and materials processing science Process metallurgy and materials processing science, 2015-04, Vol.46 (2), p.644-652
• Main Authors: Li, Mei, Liu, Yaochen, Han, Wei, Wang, Shanshan, Zhang, Milin, Yan, Yongde, Shi, Weiqun
• Format: Article
• Language: English
• Subjects: Characterization and Evaluation of Materials; Chemistry and Materials Science; Materials Science; Metallic Materials; Nanotechnology; Structural Materials; Surfaces and Interfaces; Thin Films
• ISSN: 1073-5615; 1543-1916
• DOI: 10.1007/s11663-014-0222-9

The electrochemical formation of Mg-Al-Y alloys was studied in the LiCl-NaCl-MgCl 2 melts by the addition of AlF 3 and YCl 3 on a molybdenum electrode at 973 K (700 °C). In order to reduce the volatilization of salt solvent in the electrolysis process, the volatile loss of LiCl-NaCl-MgCl 2 and LiCl-KCl-MgCl 2 melts was first measured in the temperature range from 873 K to 1023 K (600 °C to 750 °C). Then, the electrochemical behaviors of Mg(II), Al(III), Y(III) ions and alloy formation processes were investigated by cyclic voltammetry, chronopotentiometry, and open circuit chronopotentiometry. The cyclic voltammograms indicate that the under-potential deposition of magnesium and yttrium on pre-deposited Al leads to formation of Mg-Al and Al-Y intermetallic compounds. The Mg-Al-Y alloys were prepared by galvanostatic electrolysis in the LiCl-NaCl-MgCl 2 -AlF 3 -YCl 3 melts and characterized by X-ray diffraction and scanning electron microscopy with energy dispersive spectrometry. Composition of the alloys was analyzed by inductively coupled plasma-atomic emission spectrometer, and current efficiency was also determined by the alloy composition.