In a method of manufacturing a permanent magnet having a curved surface, a permeating material including metal particles and a flux is applied to the curved surface of a magnet. The magnet to which the permeating material is applied is then positioned within a furnace and the furnace is placed in a vacuum or filled with inert gas to volatilize a solvent and the like of the flux contained in the permeating material. The furnace is set to be a temperature within a range of 300 through 500 degrees C. to heat the permeating material. This enables the flux to be carbonized to form reticulated carbon. The furnace is then set to be a temperature within a range of 500 through 800 degrees C. to melt the metal particles in the permeating material, thereby permeating the melted metal particles into the magnet through the reticulated carbon uniformly.

The current invention discloses a type of micronized powder for manufacturing sintered Neodymium magnetic material, a target type jet mill pulverization method to prepare the micronized powder, and the resulting pulverized powder. The Neodymium magnet powder created under the method is of sphericity of greater than or equal to 90% and of particle adhesion rate of less than or equal to 10%. A is the diameter of the target center, B is the diameter of the side nozzle, and C is the distance between the target center and the nozzle. The relationship amongst A, B and C is A/B=m(C/A+B), where m ranges from 1 to 7. A velocity of the jet stream from side nozzle is between about 320 m/s to about 580 m/s.

According to an embodiment, a superconductor includes a base member, and a superconducting layer provided on the base member. The superconducting layer has a first surface on the base member side, and a second surface on the side opposite to the first surface. The lattice constant of the base member substantially matches the lattice constant of the superconducting layer. The superconducting layer includes REA.sub.1-xREB.sub.xBa.sub.2Cu.sub.3O.sub.7-z. The x is not less than 0.01 and not more than 0.40. The z is not less than 0.02 and not more than 0.20. The REA includes at least one of Y, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, or Lu. The REB includes at least one of Nd or Sm. The superconducting layer includes a first surface-side region including a portion of the first surface. The first surface-side region includes a first region having an orientation property, and a second region.

An R-T-B permanent magnet that contains: main-phase grains composed of an R.sub.2T.sub.14B compound (where R is a rare earth element, T is a transition metal element, and B is boron); and grain boundaries. R includes Ce. The grain boundaries include multi-grain grain boundaries that are adjacent to three or more main-phase grains. The multi-grain grain boundaries include an R-rich phase, and lamellar or acicular R-T precipitates are present in the R-rich phase.

The present application relates to a technical field of determining an irreversible demagnetization of a grain boundary diffusion NdFeB magnet, and more particularly, to a method for identifying an irreversible demagnetization of a grain boundary diffusion NdFeB magnet by magnetic field distribution. After applying a reverse magnetic field to a saturatedly magnetized grain boundary diffusion NdFeB magnet, if a number of magnetic poles on a non-diffusion face of the grain boundary diffusion NdFeB magnet is increased, it is determined that there is an irreversible demagnetization in the grain boundary diffusion NdFeB magnet.

A neodymium-iron-boron magnet is provided. The neodymium-iron-boron magnet is subject to diffusion and permeation of a heavy rare earth element, the neodymium-iron-boron magnet includes a heavy-rare-earth diffusion region at a surface layer and a core non-diffusion region, and the neodymium-iron-boron magnet has the heavy-rare-earth diffusion region at regions, which have normal directions consistent with three axes of a three-dimensional Cartesian coordinate system, of the surface layer. The present application extends the principle of diffusion from microscopic grains to macroscopic magnets. Diffusion layers of different depths may be obtained by adjusting temperature and time of heat treatment. Through the magnetic hardening of the surface layer of the magnet, the coercive force of the magnet is increased, and the magnet remanence (Br) and the maximum magnetic energy level (BHmax) are very slightly reduced. The producing process is simple, and highly controllable.

A method of processing NdFeB magnetic powder comprises: providing a source of hydrogenated NdFeB powder (101, 102, 103); feeding said powder into an inlet of a cyclone separator (104); separating the powder into an overflow enriched in Nd-rich grain boundary phase and an underflow enriched in Nd.sub.xFe.sub.yBH.sub.z matrix phase particles (106); optionally feeding the underflow back into the inlet of the cyclone separator whereby to further enrich the underflow in the Nd.sub.xFe.sub.yBH.sub.z matrix phase particles (108a); and collecting the underflow (108).

There is provided a method for manufacturing a rare earth sintered magnet by many times repetitively finely pulverizing a rare earth alloy on a jet mill by supplying high-pressure nitrogen gas to narrow grain size distribution to make an easy alignment in a magnetic field, and by micronizing crystal grains by using a hydrogenation-disproportionation-desorption-recombination (HDDR) process, to improve the coercivity and thermostability of the rare earth sintered magnet.

A method and a plant for the production of a powdery material, which is provided for the manufacture of rare earth magnets. First of all, at least one magnetic or magnetizable raw material, respectively, is provided and is comminuted into a powdery intermediate product, which includes powder particles including corners and edges, by means of conventional comminuting methods. The sharp-edged powder particles are chamfered subsequently. The optimized powdery product including the chamfered powder particles is used for the manufacture of rare earth magnets.

A method for producing an RFeB system magnet with high coercivity by preventing a coating material from peeling off the surface of a base material during a grain boundary diffusion treatment is provided. A method for producing an R.sup.L.sub.2Fe.sub.14B system magnet which is a sintered magnet or a hot-deformed magnet containing, as the main rare-earth element, a light rare-earth element R.sup.L which is at least one of the two elements of Nd and Pr, the method including: applying, to a surface of a base material M of the R.sup.L.sub.2Fe.sub.14B system magnet, a coating material prepared by mixing a silicone grease and an R.sup.H-containing powder containing a heavy rare-earth element R.sup.H composed of at least one element selected from the group of Dy, Tb and Ho; and heating the base material together with the coating material. Improved coating and base materials adhesion facilitates transfer of R.sup.H into base material grain boundaries.