Provided is a magnet that allows the orientation direction of main and auxiliary pole pieces to be set precisely and enables easy fabrication of flux focusing permanent magnet units having a high magnetic flux density A magnet 22 includes permanent magnet units 22a each including a main pole piece 221 and auxiliary pole pieces 222. The main pole piece 221 is composed of permanent magnet sheets 221a with substantially the same thickness stacked in the thickness direction. The auxiliary pole pieces 222 are composed of permanent magnet sheets 222a with substantially the same thickness stacked in the thickness direction and arranged at positions adjacent to the main pole piece 221 with orientation directions different from the orientation direction of the main pole piece 221 thereby to focus the magnetic flux at the main pole piece 221.

A magnet structure includes columnar grains of rare earth permanent magnet phase aligned in a same direction and arranged to form bulk anisotropic rare earth alloy magnet having a boundary defined by opposite ends of the columnar grains and lacking triple junction regions, and rare earth alloy diffused onto opposite ends of the bulk anisotropic rare earth alloy magnet.

A method and a plant for the production of a powdery starting material, which is provided for the manufacture of rare earth magnets, are disclosed. First of all, at least one magnetic material, which is comminuted into a powdery intermediate product with a possibly increased concentration of impurities, and/or at least one alloy including rare earth metal are provided, which includes a low concentration of impurities. A classification of the powdery intermediate product to at least one criterion takes place subsequently, wherein, for the classification of the powdery intermediate product with the increased concentration of impurities, at least one dynamic classifier is provided, which divides the powdery intermediate product with impurities into at least two fractions based on the at least one criterion, wherein at least a high concentration of impurities accumulates in a first fraction and no impurities or at least a lower concentration of impurities than in the case of the first fraction accumulate in a second fraction, and wherein the fraction without impurities or with a low concentration of impurities forms the starting material for the manufacture of rare earth magnets.

The invention relates to a unitary magnet (1) that has an elongate shape and an at least partially ovoid contour as the unitary magnet (1) comprises a first portion (1a) forming a body of the unitary magnet (1) that has a larger cross-section and extends over a greater portion of the length of the unitary magnet (1) than at least one second longitudinal end portion (1b) that points towards an associated longitudinal end of the magnet and has a decreasing cross-section towards the longitudinal end.

A method and apparatus for automatically repairing structure cracks. The method may include mixing a filler material with ferromagnetic dust to create a filler material mixture. The method may also include storing each filler material mixture in a filler material reservoir. The method may also include creating an array of magnetic coils in the structure, where the array of magnetic coils creates a magnetic path through the structure. The apparatus may include a structure. The structure may include a plurality of filler material reservoirs, wherein each filler material reservoir stores a filler material mixture. The structure may also include an array of magnetic coils inside the structure.

The invention relates to a method for recovery of Nd.sub.2Fe.sub.14B grains from bulk sintered Nd—Fe—B magnets and/or magnet scraps. In this method the Nd—Fe—B magnets (1) and/or magnet scraps are anodically oxidized using a non-aqueous liquid electrolyte (5), said anodic oxidation releasing the Nd.sub.2Fe.sub.14B grains (6) in said Nd—Fe—B magnets (1) and/or magnet scraps. The released Nd.sub.2Fe.sub.14B grains (6) are collected during and/or after said anodic oxidation. The proposed method allows a more environmental friendly and cost-effective way for recycling EOL Nd—Fe—B magnets/Nd—Fe—B magnet scraps.

The present disclosure is drawn to 3D printing kits, multi-fluid kits for 3D printing, and methods of making 3D printed articles. In one example, a 3D printing kit can include a powder bed material, a fusible fluid, and a magnetic fluid. The powder bed material can include polymer particles. The fusible fluid can include water and a radiation absorber. The fusible fluid can be to selectively apply to the powder bed material. The magnetic fluid can include magnetic particles, and the magnetic fluid can be to selectively apply to the powder bed material.

A method includes depositing a layer of alloy particles including rare earth permanent magnet phase above a substrate, laser scanning the layer while cooling the substrate to melt the particles, selectively initiate crystal nucleation, and promote columnar grain growth in a same direction as an easy axis of the rare earth permanent magnet phase. The method also includes repeating the depositing and scanning to form bulk anisotropic rare earth alloy magnet with aligned columnar grains.

A system and method for recycling rare earth materials from dissimilar hard disk drives are provided. The system and method generally include scanning each hard disk drive, sorting and aligning each hard disk drive, rapid fastener removal or diversion to a metrology station, and the collection of separated value streams, optionally for formation into new magnetic stock. For each scanned hard disk drive having a match in an inventory database, the method includes the separation of an internal magnet from residual components. For each scanned hard disk drive lacking a match in the inventory database, the method includes generating a metrology data collection record containing the location of each fastener on multiple surfaces of the corresponding hard disk drive. The system and method are commercially scalable with the potential to generate between 600 and 700 metric tons of rare earth elements from a single processing facility annually, including neodymium for example.

A rare earth sintered magnet is prepared by a method comprising the steps of melting raw materials to form an alloy, pulverizing the alloy into a fine powder, shaping the fine powder into a compact, and sintering the compact. The pulverizing step includes a coarse pulverizing step including hydrogen decrepitation and a fine pulverizing step, and further includes the step of adding a lubricant. The sintering step includes an atmosphere heat treatment including heating the compact at a temperature from the lubricant decomposition temperature to the sintering temperature and holding at the temperature for a time, in an inert gas atmosphere, and a vacuum heat treatment. The sintered magnet has a low impurity concentration and a narrow carbon concentration distribution.