Method for preparing rare earth magnesium alloy and yttrium-neodymium magnesium alloy

The invention relates to a method for preparing yttrium-neodymium magnesium alloy and the yttrium-neodymium magnesium alloy. A graphite block is adopted as an anode, a molybdenum rod serves as an inertia cathode, a molybdenum crucible serves as an alloy receiver, mixtures of yttrium oxide, neodymium oxide and magnesium oxide are added into a fluoride molten salt electrolyte system composed of yttrium fluoride, neodymium fluoride and lithium fluoride, then direct currents are guided for electrolysis and finally the yttrium-neodymium magnesium alloy is obtained; the mass ratio of the yttrium fluoride to the neodymium fluoride to the lithium fluoride in the fluoride molten salt electrolyte system is 5-20 to 70-90 to 5-10, the mass percent ratio of the neodymium oxide and the yttrium oxide to the magnesium oxide is 99-80 to 1-20, the mass percent ratio of the neodymium oxide to the yttrium oxide is 99-1 to 1-99, and the electrolysis temperature ranges from 1050 DEG C to 1150 DEG C. The method has the advantages t