Magnet Recycling to Create Nd-Fe-B Magnets with Improved or Restored Magnetic Performance

Abstract

Recycled Nd—Fe—B sintered magnets. One of the recycled Nd—Fe—B sintered magnets includes a composition of WaRbAc, where waste material W comprises material from a waste Nd—Fe—B sintered magnet, rare earth material R comprises at least one of: Nd or Pr, and elemental additives A comprises at least one of: Nd, Pr, Dy, Co, Cu, or Fe, and indices a, b, and c indicate atomic percentages of the corresponding compositions or elements and have values satisfying Nd[0.1-19 at. %*s(Nd), x]Pr[0.1-19 at. %*s(Pr),y]Dy[0.1-19%*s(Dy),z]Co[0,d]Cu[0,e]Fe[0,f] where [m, n] means a range from minimum m and maximum n, s(t) is the atomic percent of element t in starting composition; f(t) is the atomic percent of element t in final composition, x=18−[81, 99.9] at. %*(s(Nd)+s(Pr)+s(Dy)), y=18−[81, 99.9] at. %*(s(Nd)+s(Pr)+s(Dy)), z=18−[81, 99.9] at. %*(s(Nd)+s(Pr)+s(Dy)), d=3−[81, 99.9] at. %*s(Co), e=0.3−[81, 99.9] at. %*s(Cu), and f=77−[81, 99.9] at. %*(s(Fe)+s(Co)).

Dependencies are inferred from the claim text.