Recycling of waste Nd-Fe-B sintered magnets by doping with dysprosium hydride nanoparticles

Abstract Recycling of waste sintered Nd-Fe-B permanent magnets by doping DyH 3 nanoparticles was investigated. The effect of the DyH 3 nanoparticles on the microstructure and magnetic properties of the recycled magnets was studied. As the DyH 3 nanoparticles additive increased, the coercivity of recycled magnet increased gradually. The recycled magnets with DyH 3 nanoparticle content between 0.0 wt.% and 1.0 wt.% maintained the remanence ( B r ), but, with higher additions, the B r began to decrease rapidly. The best recycled magnet produced contained 1.0 wt.% of DyH 3 nanoparticles when compared to the properties of the starting waste sintering magnet. The H cj , B r and ( BH ) max values of 101.7%, 95.4%, and 88.58%, respectively, were recovered.