A permanent-magnet synchronous motor or generator with at least one rotor (2) and at least one stator (3, 8). The motor includes two rotors (2), four stators (3, 8) and a cooling system (7, 7a). The cooling system includes three cooling circuits (7, 7a), i.e. two outer circuits (7) which are each accommodated in a longitudinal outer wall of a casing (8), adjacent to an outermost stator (3, 8), for cooling said outermost stator (3, 8), and an intermediate circuit (7a) located between the two innermost stators (3, 8) in the motor for simultaneously cooling said two stators (3, 8), the central shaft (5) being common to the two rotors (2) which are connected to the central shaft (5) by mechanical means.

A magnet and a method of forming the magnet are provided. The method includes forming a slurry comprising magnetic powder material and binder material and creating raw layers from the slurry. A magnetic field is applied to the raw layers to orient the magnetic powder material in a desired direction, and each layer is cured to form another layer on the most recent cured layer. The layers are attached together.

Disclosed is a method of magnetising a substrate comprising the steps of: preparing a magnetising coat by dispersing a plurality of particles of at least one magnetisable material in a binder; applying the magnetising coat on a surface of the substrate; setting the magnetising coat; and magnetising the magnetisable material in the magnetising coat by exposing the magnetising coat to a magnetic field.

A sintered magnet, the sintered magnet including a core portion, a shell portion arranged at an outer part of the sintered magnet, and a diffusion portion arranged at least partially between the core portion and the shell portion. The shell portion has a coercivity, which is at least 30 kA/m larger than the coercivity of the core portion. In the diffusion portion, the coercivity is not less than the coercivity of the core portion and not larger than the coercivity of the shell portion and the value of the coercivity gradually increases from the core portion towards the shell portion. The thickness of the core portion is not less than 1 mm and the total thickness of the shell portion and the diffusion portion is at least 5 mm.

When a slurry s obtained by dispersing a rare-earth-compound powder in a solvent is applied to sintered magnet bodies m, and dried to remove the solvent in the slurry and cause the surfaces of the sintered magnet bodies to be coated with the powder, and the sintered magnet bodies coated with the powder are heat treated to cause the rare-earth element to be absorbed by the sintered magnet bodies, the sintered magnet bodies m are warmed or heated before the slurry s is applied. As a result, the rare-earth-compound powder can be efficiently and uniformly applied to the surfaces of the sintered magnet bodies.

A sintered R-T-B based magnet work contains R: 27.5 to 35.0 mass % (R is at least one rare-earth element which always includes Nd), B: 0.80 to 0.99 mass %, Ga: 0 to 0.8 mass %, M: 0 to 2 mass % (M is at least one of Cu, Al, Nb and Zr), and a balance T (T is at least one transition metal element which always includes Fe, with 10% or less of Fe replaceable by Co). [T]/55.85>14[B]/10.8 is satisfied where [T] is the T content (mass %) and [B] is the B content (mass %). At least a portion of a Pr—Ga alloy is in contact with a portion of the sintered magnet work surface, and a first heat treatment is performed at a temperature between 600° C. and 950° C. A second heat treatment is performed at a temperature lower than the temperature of the first heat treatment and between 450° C. and 750° C.

A sintered R-T-B based magnet work contains R: 27.5 to 35.0 mass % (R is at least one rare-earth element which always includes Nd), B: 0.80 to 0.99 mass %, Ga: 0 to 0.8 mass %, M: 0 to 2 mass % (M is at least one of Cu, Al, Nb and Zr), and a balance T (T is at least one transition metal element which always includes Fe, with 10% or less of Fe replaceable by Co). [T]/55.85>14[B]/10.8 is satisfied where [T] is the T content (mass %) and [B] is the B content (mass %). At least a portion of a Pr—Ga alloy is in contact with a portion of the sintered magnet work surface, and a first heat treatment is performed at a temperature between 600° C. and 950° C. A second heat treatment is performed at a temperature lower than the temperature of the first heat treatment and between 450° C. and 750° C.

The present invention provides a method for manufacturing a rare-earth magnet, the method comprising the steps of preparing a rare-earth magnet raw material powder including R, Fe and B as composition components (R is one or more elements selected from the rare earth elements including Y and Sc); packing the raw material powder into a molding die, and compacting and molding the raw material powder while applying a magnetic field, wherein, in the compacting and molding step, compacting is performed biaxially, in the directions of X and Y axes, when the magnetic field is applied in the direction of Z axis.

The present invention provides a method for manufacturing a rare-earth magnet, the method comprising the steps of preparing a rare-earth magnet raw material powder including R, Fe and B as composition components (R is one or more elements selected from the rare earth elements including Y and Sc); packing the raw material powder into a molding die, and compacting and molding the raw material powder while applying a magnetic field, wherein, in the compacting and molding step, compacting is performed biaxially, in the directions of X and Y axes, when the magnetic field is applied in the direction of Z axis.

The magnetic tape includes a non-magnetic support; a magnetic layer including ferromagnetic powder and a binding agent on one surface side of the non-magnetic support; and a back coating layer including non-magnetic powder and a binding agent on the other surface side of the non-magnetic support, in which an isoelectric point of a surface zeta potential of the magnetic layer is equal to or smaller than 3.8, and an isoelectric point of a surface zeta potential of the back coating layer is equal to or smaller than 3.0, a magnetic tape cartridge, and a magnetic tape apparatus including this magnetic tape.