Study on Vacuum Suction Casting Technology for Pr-Nd Metal

Pr-Nd metal is a precursor for preparation of Nd-Fe-B materials. The method of Pr-Nd preparation mainly as molten salt electrolysis. At present, the method of tapping for Pr-Nd metal includes mainly as artificial scooping and crucible lifting in the molten salt electrolysis process. However, long working time and heavy workload, it is difficult to meet the high standards of intelligent manufacturing in rare earth industry and the high quality of Pr-Nd metal in advanced materials. A complete set of equipment for preparing rare earth metals was designed and produced on the basis of principle of vacuum suction casting in this study. After studying on experimental results of producing rare earth fluoride by 15 kA electrolyzer on vacuum suction casting, this paper focuses on inspection of stability and adaptability of the equipment. Meanwhile, the paper also discusses the differences of electrolysis process and metal quality by vacuum suction casting and artificial spooning-out process. The results show that the metal time significantly shortened, small temperature fluctuations, metal purity prepared by vacuum suction casting and quality uniformity is good with fewer impurities. The equipment operates stably, have the characteristics of miniaturization, mechanization, simple and portable and can be used in 10 kA and more rare earth molten salt electrolyzer.