An electrochemical method was used to prepare Mg-Li-La alloys in a molten LiCl-KCl-KF-MgCl2 containing La2O3 at 943 K. The results showed preparation of Mg-Li-La alloys by electrolysis is feasible. The Mg-Li-La alloys were analyzed by means of X-ray diffraction （XRD）, optical micrograph （OM） and scanning electron microscopy （SEM）. XRD analysis indicates that α＋Mg17La2, α＋β＋Mg17La2 and β＋LaMg3 Mg-Li-La alloys with different lithium and lanthanum contents were obtained via galvanostatic electrolysis. The microstructures of typical α＋Mg17La2 and β＋LaMg3 phases of Mg-Li-La alloys were characterized by optical microscopy （OM） and scanning electron microscopy （SEM）. The analysis of energy dispersive spectrometry （EDS） shows that the element of Mg distributes homogeneously in the Mg-Li-La alloy and the element of La mostly exists at grain boundaries to restrain the grain growth rate due to the larger ionic radius and lower electronegativity compared with Mg.
Direct electrodeposition of quarternary Mg-Zn-Li-Ca alloys on a molybdenum electrode from LiCl-KCl-MgCl2-ZnCl2-CaCl2 melts at 943 K was investigated.Cyclic voltammograms（CVs） show that the deposition potential of Li shifts in a positive direction after adding MgCl2,ZnCl2 and CaCl2.Chronopotentiometric measurements indicate that the codepositon of Mg,Li,Zn,and Ca occurs at current densities lower than-1.55 A/cm2.X-ray diffraction（XRD） indicates that Mg-Zn-Li-Ca alloys with different phases were prepared via galvanostatic electrolysis.The microstructures of typical phase of Mg-Zn-Li-Ca alloys were characterized by optical microscopy（OM） and scanning electron microscopy（SEM）.The analysis of energy dispersive spectrometry（EDS） shows that elements of Mg and Ca distribute homogeneously in the Mg-Zn-Li-Ca alloy.However,element Zn mainly locates at the edges of the domain.
Cyclic voltammetry and chronopotentiometry were used to study the reaction mechanism of Pb（Ⅱ） and the co-deposition of Pb,Mg and Li on molybdenum electrodes in LiCl-KCl-PbCl2-MgCl2 melts.The diffusion coefficient of lead ions in the melts was determined by different electrochemical techniques.The results obtained by cyclic voltammetry and chronopotentiometry indicated that the underpotential deposition of lithium on pre-deposited Pb leads to the formation of a liquid Li-Pb alloy,and the Mg-Li-Pb alloys are formed after the addition of MgCl2.X-ray diffraction confirmed that in the Mg-Li-Pb alloy,PbLi3,Mg2Pb and Li7Pb2 phases exist by galvanostatic electrolysis at 6.21 A/cm2 for 2 h at 873 K and the phases can be controlled by changing the concentration of PbCl2 and MgCl2.
An electrochemical approach for the preparation of Mg-Li-Y alloys via co-reduction of Mg, Li, and Y on a molybdenum electrode in LiCl-KCl-MgCl2-YCl3 melts at 943 K was investigated. Cyclic voltammograms （CVs） illuminated that the underpotential deposition （UPD） of yttrium on pre-deposited magnesium led to the formation of a liquid Mg-Y alloy, and the succeeding underpotential deposition of lithium on pre-deposited Mg-Y led to the formation of a liquid Mg-Li-Y alloy. Chronopotentiometry measurements indicated that the order of electrode reactions was as follows： discharge of Mg（II） to Mg-metal, electroreduction of Y on the surface of Mg with formation of ε-Mg24＋xY5 and after that the discharge of Li＋ with the deposition of Mg-Li-Y alloys. X-ray diffraction （XRD） indicated that Mg-Li-Y alloys with different phases were formed via galvanostatic electrolysis. The microstructure of different phases of Mg-Li-Y alloys was characterized by optical microscope （OM） and scanning electron microscopy （SEM）. The analysis results of inductively coupled plasma atomic emission spectrometer （ICP-AES） showed that the chemical compositions of Mg-Li-Y alloys corresponded with the phase structures of the XRD patterns, and the lithium and yttrium contents of Mg-Li-Y alloys depended on the concentrations of MgCl2 and YCl3 .
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.
在803 K LiCl-KCl熔盐中,研究了通过添加助剂AlCl3直接电化学还原Sm2O3和Al-Sm合金的形成。以SmCl3为原料作为参照,采用循环伏安和方波伏安方法,研究了Sm2O3在LiCl-KCl-AlCl3熔盐体系中的电化学行为。通过对比发现在两个体系中,峰的数量和位置基本一致,这说明在LiCl-KCl熔盐中,加入AlCl3之后,可以将Sm2O3有效氯化。计时电位结果表明,当阴极电流比-139.8 mA.cm-2更负时,Al和Sm共同还原。为了提取Sm,采用恒电流从LiCl-KCl-AlCl3-Sm2O3熔盐中电解得到Al-Sm合金样品,并进行XRD表征,结果表明可以通过调节AlCl3和Sm2O3的浓度得到不同相的Al-Sm合金。
