Recycle of Waste Nd–Fe–B Sintered Magnets via NdHx Nanoparticles Modification

The waste sintered Nd-Fe-B magnets were recycled to fabricate anisotropic bonded magnets by the combination of hydrogen decrepitation (HD) and NdH
_x
nanoparticle modification. Magnetic properties of the recycled magnetic powders and bonded magnets were investigated. Adding NdH
_x
nanoparticles to HD powders may increase the coercivity of the recycled powders. The HD powders with 10 wt. % NdH
_x
degassed at 973 K for 5 h bear magnetic properties of Br of 9.36 kGs and H
_ci
of 12.36 kOe. The recycled bonded magnet exhibits good magnetic properties of B
_r
= 7.61 kGs, H
_ci
= 12.93 kOe, and (BH)
_max
= 11.56 MGOe.