This paper presented a novel study on electrochemical codeposition of Mg-Li-Yb alloys in LiCl-KCl-KF-MgCl2-Yb2O3 melts on molybdenum. The factors of the current efficiency were investigated. Electrolysis temperature had great influence on current efficiency; the highest current efficiency was obtained when electrolysis temperature was about 660 oC. The content of Li in Mg-Li-Yb alloys increased with the high current densities. The optimal electrolytic temperature and cathodic current density were around 660 oC and 9.3 A/cm2, respectively. The chemical content, phases, morphology of the alloys and the distribution of the elements were analyzed by X-ray diffraction, scanning electron microscopy, inductively coupled plasma mass spectrometry, respectively. The intermetallic of Mg-Yb was mainly distributed in the grain boundary of the alloys, presented as reticulated structures, and refined the grains. The lithium and ytterbium contents in Mg-Li-Yb al-loys could be controlled by changing the concentration of MgCl2 and Yb2O3 and the electrolysis conditions.
