Abstract: The present disclosure discloses a cerium-added RE-T-B-M series sintered neodymium-iron-boron magnet, which relates to the technical field of neodymium-iron-boron permanent magnets, the structure of the magnet contains a RE2Fe14B main phase, a RE-rich phase, a REFe2 phase, and a sandwich grain boundary phase, wherein the sandwich grain boundary phase includes a RE-rich phase, a Fe-rich phase, and a REFe2 phase, and in the sandwich grain boundary phase, starting from the side near the grains of RE2Fe14B main phase, the first layer is the RE-rich phase, the second layer is the Fe-rich phase, and the third layer is the REFe2 phase, where RE includes cerium element and at least one of other rare earth elements, and the cerium element accounts for 3.0-15.0% by mass of the total elements, T is iron element and cobalt element, B is boron element, and M is Al, Cu, Ga, and Ti elements.

Abstract: The disclosure provides a preparation method, which comprises: providing a moulding die for a ring-shaped sintered Nd—Fe—B magnet; placing a Nd—Fe—B magnetic powder into the mould cavity of the moulding die in a loosely packed state, the loosely packed height of the Nd—Fe—B magnetic powder is L; placing a flexible cylindrical core into the loosely packed Nd—Fe—B magnetic powder at a L/2 position, wherein an axial direction of the flexible cylindrical core is horizontal and parallel to the direction of a magnetic field in the mould cavity; applying a vertical pressure to the Nd—Fe—B magnetic powder to obtain a ring-shaped green block assembly with the flexible cylindrical core embedded; after encapsulating and isolating the ring-shaped green block assembly, applying an isostatic pressure to the ring-shaped green block assembly; sintering the ring-shaped green block assembly to obtain a ring-shaped sintered blank; thermally aging, grinding and slicing the ring-shaped sintered blank.

Abstract: The present disclosure provides a rare earth magnet and manufacturing method thereof, which belongs to the field of rare earth magnet technology. The diffusion source is coated on the NdFeB base material, which is diffused and aged to obtain NdFeB magnet. The diffusion source alloy is R?M?B?Fe100-?-?-?, wherein R refers to at least one of Nd and Pr, and M Refers to at least one of Al, Cu, Ga. The Br reduction range is lower than 0.03 T, and Hcj growth is more than 318 kA/m.

Abstract: The present disclosure provides an NdFeB rare earth magnet and manufacturing method thereof, which belongs to the field of rare earth magnet technology. The production method of diffusion source is to coat a layer of non-heavy rare earth alloy film on the diffusion source sheet, and aging treatment are carried out to form diffusion source. The diffusion source is R?RH?M?B?Fe100-?-?-?-?. The chemical formula of the non-heavy rare earth alloy film is RnMm. The chemical formula of NdFeB magnet base material is RaM1bM2cBdFe100-a-b-c-d. The performance NdFeB by diffusion source containing Dy have ?Hcj>636.8 kA/m and containing Tb have ?Hcj>875.6 kA/m, containing DyTb have ?Hcj>716.4 kA/m.

Abstract: The present disclosure refers to a method for preparing sintered NdFeB magnets, including: a) Preparing alloy flakes from a raw material by strip casting, performing a hydrogen decrepitation to produce alloy pieces, pulverization the alloy pieces to an alloy powder, performing molding and orientation, cold isostatic pressing, and getting a green compact; b) Putting the green compact into a vacuum furnace and performing a first sintering step in 830 to 880° C. for 2 to 10 hours and 5×10?1 Pa or less; c) Performing a second sintering step while applying a pressure to the green compact achieved by step b), the pressure is 1 MPa to 5 MPa and the sintering temperature is 720 to 850° C. for 15 to 60 minutes, and the temperature of the first sintering step is at least 10° C. higher than that of the second sintering step; d) Subjecting the sintered magnet of step c) to an annealing treatment.

Abstract: The disclosure refers to a method for preparing NdFeB magnets including at least one of Ce and La. The method includes: S1) Separately preparing flakes of alloy R1 and flakes of alloy R2 each by a strip casting process, wherein the alloy R1 includes at least one of La and Ce, but the alloy R2 does not include La and Ce; S2) separately subjecting the flakes of alloy R1 and R2 to a hydrogen embrittlement process followed by pulverizing the process product to alloy powders by jet milling, wherein a ratio of the average particle sizes D50 of the powder of alloy R1 and R2 satisfied formula: 0.32?R2/R1?0.66; S3) mixing the powder of alloy R1 and R2; and S4) subjecting the mixed powders to molding and magnetic field orientation, cold isostatic pressing, sintering, and an annealing process.

Abstract: The present disclosure refers to a method for preparing sintered NdFeB magnets, including: a) Preparing alloy flakes from a raw material by strip casting, performing a hydrogen decrepitation to produce alloy pieces, pulverization the alloy pieces to an alloy powder, performing molding and orientation, cold isostatic pressing, and getting a green compact; b) Putting the green compact into a vacuum furnace and performing a first sintering step in 830 to 880° C. for 2 to 10 hours and 5×10?1 Pa or less; c) Performing a second sintering step while applying a pressure to the green compact achieved by step b), the pressure is 1 MPa to 5 MPa and the sintering temperature is 720 to 850° C. for 15 to 60 minutes, and the temperature of the first sintering step is at least 10° C. higher than that of the second sintering step; d) Subjecting the sintered magnet of step c) to an annealing treatment.

Abstract: The disclosure provides a preparation method, which comprises: providing a moulding die for a ring-shaped sintered Nd—Fe—B magnet; placing a Nd—Fe—B magnetic powder into the mould cavity of the moulding die in a loosely packed state, the loosely packed height of the Nd—Fe—B magnetic powder is L; placing a flexible cylindrical core into the loosely packed Nd—Fe—B magnetic powder at a L/2 position, wherein an axial direction of the flexible cylindrical core is horizontal and parallel to the direction of a magnetic field in the mould cavity; applying a vertical pressure to the Nd—Fe—B magnetic powder to obtain a ring-shaped green block assembly with the flexible cylindrical core embedded; after encapsulating and isolating the ring-shaped green block assembly, applying an isostatic pressure to the ring-shaped green block assembly; sintering the ring-shaped green block assembly to obtain a ring-shaped sintered blank; thermally aging, grinding and slicing the ring-shaped sintered blank.

Abstract: The present disclosure relates to a method for preparing high-performance sintered NdFeB magnets. The method comprises the steps of: a) attaching a multi-element alloy powder onto a surface of the sintered NdFeB magnet, wherein the multi-element alloy is of formula (1) PraRHbGacCud (1) with RH being at least one element selected from Dy and Tb and a, b, c, and d satisfying the conditions 0.30?(a+b)/(a+b+c+d)?0.65, 0.20?d/(c+d)?0.50, and 0.23?b/(a+b)?0.60; and b) performing a diffusion process.

Abstract: The disclosure provides a method for preparing a radiation-oriented sintered arc-shaped Nd—Fe—B magnet. The method comprises: providing a Nd—Fe—B powder and a molding device; performing a first sub-step of align pressing including filling the arc-shaped cavity of the molding device with a first powder loading of the Nd—Fe—B powder, performing a first magnetization of the Nd—Fe—B powder, and mold pressing the Nd—Fe—B powder to form a first green body; performing a second sub-step of align pressing including filling the arc-shaped cavity of the molding device with a second powder loading of the Nd—Fe—B powder, performing a second magnetization of the Nd—Fe—B powder, and mold pressing the Nd—Fe—B powder to form a second green body; and sintering and annealing the second green body to obtain an arc-shaped Nd—Fe—B magnet. Further aspects of the disclosure are a molding device useful for the preparation method and a radiation-oriented sintered arc-shaped Nd—Fe—B magnet obtained by the method.

Abstract: A sintered R-T-B based permanent magnet includes a body having an easy-axis of magnetization. The body has a plurality of R2T14B main phases spaced from one another and a plurality of grain boundary phases between the R2T14B main phases. The body including zero heavy rare earth elements and the grain boundary phases includes a first and a second grain boundary phase. The first grain boundary phase is disposed between the R2T14B main phases and extends along and parallel to the easy-axis of magnetization whereby the first grain boundary phase forms a plurality of first grain boundary triple point areas with the first grain boundary triple point areas being a rare earth element rich phase having a high content of Al and Ga and includes 65 at. %?Pr+Nd?88 at. %, 10 at. %?Al+Ga?25 at. %, O?10 at. %, and Fe+Cu+Co?2 at. %. A method of making the sintered R-T-B based permanent magnet is disclosed herein.

Abstract: Disclosed is a method of manufacturing a rare earth permanent magnet with substantially improved magnetic property. The method comprises: preparing a magnet master alloy by melting an R-T-B based alloy; pulverizing the magnet master alloy to provide a magnet powder; pressurizing the magnet powder as applying magnetic field to the magnet powder under an inert atmosphere to form a magnet molded body; sintering the magnet molded body under a vacuum atmosphere to obtain a sintered magnet molded body having oxygen content of about 0.1 wt % or less based on the total weight of the sintered magnet molded body; and treating the sintered magnet molded body with Dy and Tb.