The formation and dissolution of aluminum carbide is considered the primary factor affecting the life of aluminum electrolysis cells. Herein, the characteristics of sodium-graphite intercalation compounds (Na-GICs)were measured and the formation mechanism of Al4C3duringthe aluminum electrolysis process was experimentally studied. The Na-GIC characteristics and the products of aluminum and Na-GIC reactions were investigated by Raman spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy and scanning electron microscopy. The results showed that graphite can react with the sodium metal to form Na-GICs, which were detectable by Raman spectroscopy. Sodium that inserted into the graphite layered structure acted as an intercalation agent to change the original graphite layered structure and increase the volume and specific surface area of graphite. Further, Al4C3wasproduced by using sodium-graphite intercalation compounds and aluminum as materials. Thus, the presence of sodium plays an important role in the formation process of Al4C3in aluminum electrolysis cells.

Mg-Li alloys are the lightest metallic construction materials and one of the most representative light alloys. The process of producing Mg-Li alloys by vacuum aluminothermic reduction, using magnesite and lithium carbonate as raw materials, was studied. The influence of reduction parameters on the extents of reduction of MgO and Li 2 O was investigated. The results show that Mg-Li alloys can be produced by vacuum aluminothermic reduction using calcined magnesite and lithium carbonate. MgO was relatively easier to reduce by aluminum than Li 2 O. Almost all MgO was reduced to Mg and more than 96% of Li 2 O was reduced to Li. The main phase in the reduction slag was Li 2 O•5Al 2 O 3. The reaction mechanism was discussed. Vacuum aluminothermic reduction can be considered as a highly efficient and environmental friendly method for producing Mg-Li alloys.