Disclosed are an RFeB-based sintered magnet with a low B content and a preparation method therefor. The sintered magnet comprises the following components: 28.5 wt %-31.5 wt % of R, 0.86 wt %-0.94 wt % of B, 0.2 wt %-1 wt % of Co, 0.2 wt %-0.45 wt % of Cu, 0.3 wt %-0.5 wt % of Ga, 0.02 wt %-0.2 wt % of Ti, and 61 wt %-69.5 wt % of Fe. The sintered magnet has an R.sub.6-T.sub.13M.sub.1+ series phase accounting for 75% or more of the total volume of grain boundaries. The present invention selects optimal content ranges of R, B, Co, Cu, Ga, and Ti, and forms an R.sub.6-T.sub.13M.sub.1+ series phase of a special composition and increases its volume fraction in grain boundary phases, so as to acquire higher Hcj and SQ values.

A method of producing an oppositely magnetized magnetic structure within or on a substrate material includes: First and second numbers of cavities are generated within or on a substrate material and are filled with first and second hard magnetic materials, respectively, exhibiting first and second coercive field strengths, respectively, so as to produce first and second arrangements of hard magnetic structures, respectively, the second coercive field strength being smaller than the first coercive field strength.

The first and second arrangements of hard magnetic structures are magnetized in a first direction by a first magnetic field exhibiting a field strength which exceeds the first and second coercive field strengths.

The second arrangement of hard magnetic structures is magnetized in a second direction, which differs from the first direction, by a second magnetic field exhibiting a field strength which falls below the first coercive field strength but exceeds the second coercive field strength. Magnetizing the second arrangement of hard magnetic structures includes exposing the first and second arrangements of hard magnetic structures to the second magnetic field.

A method of manufacturing an SmFeN magnet includes a sealing step of filling a metal sheath with a magnet powder including an SmFeN compound as a main component and sealing the metal sheath, a Magnetic field applying step of applying a magnetic field to the magnet powder sealed in the metal sheath, and magnetizing the magnet powder by magnetically orienting the magnet powder and aligning a direction of magnetic orientation in one direction, a preliminary rolling step of preliminarily rolling the magnetically oriented magnet powder sealed in the metal sheath to make the magnetically oriented magnet powder into a green compact, and a pressurizing step of pressurizing the green compact sealed in the metal sheath and densifying the green compact to form a magnet body, wherein in the preliminary rolling step, the preliminary rolling is performed by lightly rolling the magnetically oriented magnet powder sealed in the metal sheath with a pressure smaller than a pressure in the pressurizing step.

Some variations provide a permanent-magnet structure comprising: a region having a plurality of magnetic domains and a region-average magnetic axis, wherein each of the magnetic domains has a domain magnetic axis that is substantially aligned with the region-average magnetic axis, and wherein the plurality of magnetic domains is characterized by an average magnetic domain size. Within the region, there is a plurality of metal-containing grains characterized by an average grain size, and each of the magnetic domains has a domain easy axis that is dictated by a crystallographic texture of the metal-containing grains. The region has a region-average easy axis based on the average value of the domain easy axis within that region. The region-average magnetic axis and the region-average easy axis form a region-average alignment angle that has a standard deviation less than 30 within the plurality of magnetic domains. Many permanent-magnet structures are disclosed herein.

Provided are: a sintered body that forms a rare-earth magnet and is configured in a manner such that the divergence between the orientation angles of the easy axes of magnetization of magnet material particles and the orientation axis angle of the magnet material particles is kept within a prescribed range in an arbitrary micro-section of a magnet cross-section; and a rare-earth sintered magnet. This sintered body for forming a rare-earth magnet has two or more different regions exhibiting an orientation axis angle of at least 20, given that the orientation axis angle is defined as the highest-frequency orientation angle among the orientation angles of the easy magnetization axes, relative to a pre-set reference line, of a plurality of magnet material particles in a rectangular section at an arbitrary position in a plane including the thickness direction and the widthwise direction.

A dual-rotor machine comprising a dual rotor support structure rotatably connected to a frame. A stationary stator is disposed between the rotors and is fixed to the frame. An inner rotor and outer rotor, each comprising a permanent magnet Halbach array, are coaxially disposed with the stator and are rotable about the stator. In this configuration, the inner rotor channels its magnetic flux to its outside, while the outer rotor channels its magnetic flux to its inside. The magnetic flux density at the stator for the dual-rotor machine can be as high as 2 Tesla or higher for high-grade neodymium-iron-boron permanent magnet material, and the stored magnetic energy for conversion to mechanical or electrical energy available to the stator may be at least 0.5 kJ/m. The rotor Halbach arrays may comprise monolithic permanent magnets with continuously variable magnetic field direction.

A continuous method of manufacturing permanent magnets and the permanent magnets created thereby. A fine powder is created from a combination of magnetic metals. The powder (a metal alloy) is placed in a non-magnetic container of any desired shape which could be, for example, a tube. The metal alloy and tube are swaged while a magnetic field is applied. Once swaging is complete, the metal alloy and tube are sintered and then cooled. Instead of sintering, a bonding agent can mixed into the powder. Following cooling, the metal alloy is magnetized by placing it between poles of powerful electromagnets with the desired field direction. The process of the invention enables mass-produced, cost-effective PM products, which are more robust, easily assembled into products, enables new wire like shapes with arbitrary magnetization direction. The process enables mass production of permanent magnets of any desired cross section, produces permanent magnets continuously that may be cut to any length, and may, in an embodiment, result in directional magnets.

There is provided a method for manufacturing a rare earth sintered magnet having a stable magnetic performance, by uniformly distributing a heavy rear earth element to the surface of the magnet and the grain boundary inside of the magnet by using a mixture of a heavy rare earth compound or a heavy rare earth metal alloy and a rare earth magnet powder, to lower a decrease rate of the magnetic characteristics based on the temperature of the rare earth sintered magnet.

The invention pertains to advances in real-time methods in nuclear magnetic resonance by offering a new dual-frequency dynamic nuclear polarization (DNP) method that uses a microwave beam to polarize the spins of electrons and concomitantly act as a NMR transmitter.

This invention provides for a rotary electric machine that includes a rotor having a plurality of permanent magnets arranged in the circumferential direction, and in which the leakage of magnetic flux can be suppressed with a simple structure; and a rare-earth permanent magnet-forming sintered compact for forming rare-earth permanent magnets to be used in said rotary electric machine.