Anisotropic rare earth magnet powder particles include R.sub.2TM.sub.14B.sub.1-type crystals of a tetragonal compound consisting of one or more rare earth element, B, and one or more transition element, and enveloping layers containing at least Nd and Cu. Surfaces of the R.sub.2TM.sub.14B.sub.1-type crystals are enveloped by the enveloping layers. The particles has an average crystal grain diameter of 0.05 to 1 m. The particles contain, when the whole particles are taken as 100 atomic %, 11.5 to 15 atomic % of total rare earth element (Rt); 5.5 to 8 atomic % of B; and about 0.05 atomic % to about 2 atomic % of Cu. The powder particles have an atomic ratio of Cu, which is a ratio of the total number of Cu atoms to a total number of atoms of Rt, falling within the range of 1 to 6%. The powder particles do not include dysprosium Dy, Tb, Ho and Ga. Coercivity of the magnetic powder is more than 955 kA/m.

There is provided a compression-bonded magnet with a case, which can realize high magnetic properties, high corrosion resistance and high durability strength even at low cost. The compression-bonded magnet with a case is a compression-bonded magnet with a case 1, comprising: a compression-bonded magnet 2 comprising a rare earth magnet powder such as an isotropic NdFeB magnet powder and a resin binder of a thermosetting resin; a case 3 for inserting the compression-bonded magnet 2; and a sealing member 4, wherein the compression-bonded magnet 2 is formed by compression-molding a mixture comprising the rare earth magnet powder and the resin binder into a green compact and curing the resin binder contained in the green compact, the rare earth magnet powder is contained in a large amount with respect to the entire compression-bonded magnet (for example, in a volume ratio of 85% to 90%), the sealing member 4 is fixed at an insertion opening part 3a of the case 3, and the compression-bonded magnet 2 is hermetically sealed by the sealing member 4 and the case 3.

The disclosure provides a preparation method, which comprises: providing a moulding die for a ring-shaped sintered NdFeB magnet; placing a NdFeB magnetic powder into the mould cavity of the moulding die in a loosely packed state, the loosely packed height of the NdFeB magnetic powder is L; placing a flexible cylindrical core into the loosely packed NdFeB 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 NdFeB 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.

An L10-FeNi magnetic powder has an average particle size of 50 nm to 1 m, and an average value of sphericity P of 0.9 or more. The sphericity P is defined as P=Ls/Lr, where Lr is a perimeter of an L10-FeNi magnetic powder particle on an image of a microscope, and Ls is a perimeter of a perfect circle that has a same area as the L10-FeNi magnetic powder particle on the image for which Lr is calculated.

A flexible permanent magnetic material, a preparation method and an application thereof in magnetic biological effect products are provides, relating to the technical field of medical equipment. Raw materials of the flexible permanent magnetic material of the application include the following components in parts by weight: 0-70 parts of anisotropic neodymium iron boron powder and 0-40 parts of anisotropic samarium iron nitrogen powder and 3-20 parts of binder.

A high-compactness bonded rare earth permanent magnet and a preparation method thereof. Raw materials of the rare earth permanent magnet are calculated by mass percentage and include a thermosetting resin, a lubricant, a coupling agent, and the balance being a rare earth permanent magnetic powder. The preparation method includes: mixing the rare earth permanent magnetic powder with an organic solution containing the thermosetting resin to obtain a magnetic powder complex, mixing the magnetic powder complex with the lubricant, filling into a mold and compressing and molding at 12-50 T/cm.sup.2 for 0.3-10 s, demolding to obtain a green body, heating the green body at 120-200? C. and obtaining a rough blank for precision machining. The high-compactness bonded rare earth permanent magnet shortens distances among micro powder particles in the bonded magnet effectively, enhances the magnetization effect of micro powder and strengthens the interaction force thereof after magnetization.

The present invention provides: a NdFeB multilayer sintered magnet which is magnetically uniform, while having high magnetic characteristics; and a method for producing the NdFeB sintered magnet without performing a cutting step. The method of the present invention comprises the steps of: producing a NdFeB thin plate-shaped sintered magnet in which the c-axis direction of an Nd.sub.2Fe.sub.14B tetragonal compound is oriented within the main surface of the NdFeB thin plate-shaped sintered magnet, and which has a high degree of orientation of 90% or more and a thickness of 3 mm or less, without performing a cutting step, by supplying and filling an alloy powder into a mold having a structure partitioned by a plurality of partition plates arranged at a predetermined interval, applying a magnetic field in a direction parallel to a main surface of a cavity partitioned by the partition plates to orient the alloy powder, and then performing sintering, and laminating a plurality of NdFeB thin plate-shaped sintered magnets obtained by the above step.

Composite magnets such as for electrical machines in vehicles are disclosed. The composite magnets have an interface phase that is different than the magnetically-hard phase and the magnetically-soft phase to ease the transition or create a gradual transition from between the hard and soft phases of the composite magnet. The addition of, for example, an interface layer maintains or enhances performance of the magnetic properties even with higher grain sizes such as beyond the nanoscale level.

A method for preparing a rare earth anisotropic bonded magnetic powder, comprises the following steps: (1) preparing raw powder with RTBH as the main component, wherein, R is Nd or Pr/Nd, and T is a transition metal containing Fe; (2) adding La hydride or Ce hydride and copper powder to the raw powder to form a mixture; (3) subjecting the mixture to atmosphere diffusion heat treatment to give the rare earth anisotropic bonded magnetic powder.

The invention discloses a composite rare earth anisotropic bonded magnet and a preparation method thereof. The composite rare earth anisotropic bonded magnet comprises a NdFeB magnetic powder, a SmFeN magnetic powder, a binder and an inorganic nano-dispersant. The preparation method comprises steps of preparing a NdFeB magnetic powder by a HDDR method, preparing a SmFeN magnetic powder by a powder metallurgy method, mixing the NdFeB magnetic powder, the SmFeN magnetic powder, the binder and the inorganic nano-dispersant at a specific ratio to finally obtain the composite rare earth anisotropic bonded magnet. The invention, by adding an inorganic nano-dispersant, enables the full dispersion of the fine SmFeN powder during the mixing process of the binder, the NdFeB magnetic powder and the SmFeN powder, and thus makes the fine SmFeN powder and the binder evenly coated on the surface of the anisotropic NdFeB magnetic powder.