On the production of Mg-Nd master alloy from NdFeB magnet scraps

Abstract The recovering behavior of Nd rare earth (RE) element from industrial neodymium-iron-boron (NdFeB) magnet scarps has been investigated through the liquid metal extraction (LME) method. It was found that when the holding time of melt was above 15 min, it had a negligible influence on the recovery efficiency of Nd as the Nd diffusion was rapid. The optimal temperature should be below 830 °C to avoid the formation of unreducible Nd 2 O 3 within the fine NdFeB powders. The total recovery ratio of Nd was about 80% through a twice-recycling route. The impurity levels of Fe and B that generated during the reaction were acceptable due to spontaneous settling, as below 0.22% and 0.002%, respectively.

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