China’s rare earth reserves and consumption are the highest in the world. Rare earth metals and alloys play a pivotal role in the domains of permanent magnetic materials, hydrogen storage materials, luminescent materials, abrasive materials, etc. The molten salt electrolysis process is the most widely used method for producing light rare earth metals and alloys in China, with distinct advantages such as continuous production and short process flow. This article focuses on the process technology of preparing rare earth metals and alloys by electrolyzing rare earth oxides in fluoride systems. This article summarizes the effects of process parameters such as cathode and anode structures, electrolysis temperature, and current density on the direct recovery and current efficiency of the preparation of light rare earth metals (La, Ce, Pr, Nd), RE–Mg (RE for rare earth) alloys, RE–Al alloys, RE–Ni alloys, and other rare earth alloys. Meanwhile, the disadvantages of the electrolytic cells and electrode configurations that are currently used in industrial production are discussed. Accordingly, the future prospects of molten salt electrolysis technology in the preparation of rare earth metals and alloys are clarified.

An experimental device was developed with a diaphragm and NdOF was used instead of Nd₂O₃ to solve the problem of analysis errors. A more accurate method for measuring the dissolution of Nd₂O₃ in the LiF–NdF₃ molten salt system was reported.

The thermal data of the LiF-NdF₃ binary system were optimized, and the LiF-NdF₃ binary phase diagram was constructed by combining experimental measurement with phase diagram calculation technology.