A method of producing a sintered magnet is disclosed herein. In some embodiments, a method of producing a sintered magnet comprises, sintering a R—Fe—B based magnetic powder to produce a sintered magnet; wherein the R is Nd, Pr, Dy, Ce or Tb, and infiltrating a eutectic alloy into the sintered magnet, wherein the eutectic alloy contains Pr, Al, Cu and Ga, and wherein infiltration the eutectic alloy includes applying the eutectic alloy to the sintered magnet and heat-treating the sintered magnet to which the eutectic alloy is applied.

A method for producing a sintered R-T-B based magnet includes: preparing a sintered R-T-B based magnet work (R is a rare-earth element; and T is at least one selected from the group consisting of Fe, Co, Al, Mn and Si, and contains Fe with no exception); preparing an RL-RH-B-M based alloy; and a diffusion step of performing heat treatment while at least a portion of the RL-RH-B-M based alloy is attached to at least a portion of a surface of the sintered R-T-B based magnet work. In the RL-RH-B-M based alloy, the content of RL is 50 mass % or higher and 95 mass % or lower, the content of RH is 45 mass % or lower (including 0 mass %), the content of B is 0.1 mass % or higher and 3.0 mass % is lower; and the content of M is 4 mass % or higher and 49.9 mass % or lower.

A method for producing a sintered R-T-B based magnet includes: preparing a sintered R-T-B based magnet work (R is a rare-earth element; and T is at least one selected from the group consisting of Fe, Co, Al, Mn and Si, and contains Fe with no exception); preparing an RL-RH-B-M based alloy; and a diffusion step of performing heat treatment while at least a portion of the RL-RH-B-M based alloy is attached to at least a portion of a surface of the sintered R-T-B based magnet work. In the RL-RH-B-M based alloy, the content of RL is 50 mass % or higher and 95 mass % or lower, the content of RH is 45 mass % or lower (including 0 mass %), the content of B is 0.1 mass % or higher and 3.0 mass % is lower; and the content of M is 4 mass % or higher and 49.9 mass % or lower.

A method for preparing a Nd—Fe—B-based sintered magnet. The method includes: 1) providing a master alloy and an auxiliary alloy, the master alloy being a Nd—Fe—B alloy ingot or cast strip, the auxiliary alloy being a heavy rare earth alloy; 2) breaking up the master alloy using a hydrogen decrepitation process to yield a crude powder, conducting hydrogen absorption treatment on the auxiliary alloy and breaking up the hydrogenated auxiliary alloy to yield hydride particles; 3) uniformly mixing and stirring the crude powder of the master alloy and the hydride particles of the auxiliary alloy to yield a mixture; 4) milling the mixture obtained in step 3) to yield powders; 5) uniformly stirring the powders obtained in step 4) and conducting orientation forming treatment on the powders, to yield a raw body of a Nd—Fe—B based magnet; and 6) sintering the raw body of the Nd—Fe—B based magnet.

A method for preparing a Nd—Fe—B-based sintered magnet. The method includes: 1) providing a master alloy and an auxiliary alloy, the master alloy being a Nd—Fe—B alloy ingot or cast strip, the auxiliary alloy being a heavy rare earth alloy; 2) breaking up the master alloy using a hydrogen decrepitation process to yield a crude powder, conducting hydrogen absorption treatment on the auxiliary alloy and breaking up the hydrogenated auxiliary alloy to yield hydride particles; 3) uniformly mixing and stirring the crude powder of the master alloy and the hydride particles of the auxiliary alloy to yield a mixture; 4) milling the mixture obtained in step 3) to yield powders; 5) uniformly stirring the powders obtained in step 4) and conducting orientation forming treatment on the powders, to yield a raw body of a Nd—Fe—B based magnet; and 6) sintering the raw body of the Nd—Fe—B based magnet.

This disclosure is directed to sintered bodies comprising grains and a grain boundary composition, wherein: (a) the grains comprise a composition substantially represented by a formula G.sub.2M.sub.14B, where G is Nd, Dy, Pr, Tb, or a combination thereof, and M is Co, Fe, Ni, or a combination thereof, wherein the grains are optionally doped with one or more rare earth elements; and (b) the grain boundary composition is an alloy composition substantially represented by the formula: Nd.sub.8.5-12.5Dy.sub.35-45Co.sub.32-41Cu.sub.3-6.5Fe.sub.1.5-5, wherein the subscript values are atom percent relative to the total composition of the the alloy composition. Corresponding populations of particles are also disclosed

This disclosure is directed to sintered bodies comprising grains and a grain boundary composition, wherein: (a) the grains comprise a composition substantially represented by a formula G.sub.2M.sub.14B, where G is Nd, Dy, Pr, Tb, or a combination thereof, and M is Co, Fe, Ni, or a combination thereof, wherein the grains are optionally doped with one or more rare earth elements; and (b) the grain boundary composition is an alloy composition substantially represented by the formula: Nd.sub.8.5-12.5Dy.sub.35-45Co.sub.32-41Cu.sub.3-6.5Fe.sub.1.5-5, wherein the subscript values are atom percent relative to the total composition of the the alloy composition. Corresponding populations of particles are also disclosed

A method of treating rare earth metal-bearing permanent magnet scrap, waste or other material in a manner to recover the heavy rare earth metal content separately from the light rare earth metal content. The heavy rare earth metal content can be recovered either as a heavy rare earth metal-enriched iron based alloy or as a heavy rare earth metal based alloy.

A method of treating rare earth metal-bearing permanent magnet scrap, waste or other material in a manner to recover the heavy rare earth metal content separately from the light rare earth metal content. The heavy rare earth metal content can be recovered either as a heavy rare earth metal-enriched iron based alloy or as a heavy rare earth metal based alloy.

This magnetic refrigeration module includes a magnetic refrigeration operation unit which has a magnetic refrigeration material, and extends in a longitudinal direction, and a fixed magnetic field excitation unit and a variable magnetic field excitation unit which are disposed apart from each other in an outer peripheral direction of the magnetic refrigeration operation unit, in which the fixed magnetic field excitation unit applies a fixed magnetic field to the magnetic refrigeration operation unit, and the variable magnetic field excitation unit applies a variable magnetic field to the magnetic refrigeration operation unit when being in an ON state and does not apply the variable magnetic field to the magnetic refrigeration operation unit when being in an OFF state.