Abstract: A spindle motor having a stator and a rotor includes: a stator core provided in the stator having salient-poles; a stator coil arranged between the salient-poles; a rotor; and a permanent magnet provided in the rotor. The stator core includes a stack of steel sheets whose salient-poles are formed by etching. The permanent magnet includes a ferromagnetic material consisting mainly of iron. The ferromagnetic material has formed in laminae on a surface thereof a layer of a fluorine compound containing an alkali element, an alkaline earth element or a rare earth element formed in laminae. Near an interface between the ferromagnetic material and the layer of the fluorine compound, iron exists in the layer of the fluorine compound such that a basic crystal structure of the fluorine compound is not changed and the fluorine compound containing the iron exists in the layer of the fluorine compound.

Abstract: A powder compressed magnetic core, which is produced by compressing iron powder or alloy powder of which the main component is iron. A fluoride compound layer of a fluoride of a rare earth element or a fluoride of an alkaline earth metal is formed on the surface of the powder, and an under layer is formed between the fluoride layer and the iron powder or the alloy powder.

Abstract: An electric rotating machine includes a stator having a stator core provided with a teeth unit and a coil wound around each tooth in the teeth unit in a concentrated fashion and a rotor rotatably supported with air gap against the teeth unit of the stator, the rotor having a rotor core and a plurality of permanent magnets held by the rotor core, wherein the permanent magnet is a rare earth magnet made of rare earth magnetic particles bound with SiO2. Also disclosed is an automobile that includes the electric rotating machine in which the permanent magnet in the rotor is a rare earth magnet made of rare earth magnetic particles bound with SiO2, and the stator in the electric rotating machine has a stator core provided with a teeth unit and a coil wound around each tooth in the teeth unit in a concentrated fashion.

Abstract: A rare earth element magnet comprising molded magnetic powder containing at least one rare earth element, wherein a Fe rich phase covering a part or entire of the surface of particles of the magnetic powder and having a Fe atomic percentage larger than that of the magnetic powder, and an inorganic binder bonding the particles covered with the Fe rich phase.

Abstract: A manufacturing method of a magnetic core includes a first step of applying a treatment liquid for forming an insulating film to iron powder; a second step of heat-treating the iron powder to which the treatment liquid has been applied, at a temperature higher than 350 degrees; a third step of compacting the heat-treated iron powder to form a magnetic core; and a forth step of heat-treating the magnetic core at a temperature ranging from 600 degrees to 800 degrees.

Abstract: A structure of a magnet wherein a magnet consisting of a magnetic body including iron and rare earths, a plurality of fluorine compound layers or oxyfluorine compound layers are formed interior of the magnetic body, and the fluorine compound layer or oxyfluorine compound layer has a major axis which is greater than the mean particle size of the crystal grains of the magnetic body.

Abstract: A conventional method for forming an insulating film on a magnet has a difficulty in achieving sufficient improvement in magnetic characteristics due to nonuniformity of a coating film, and an extended time and higher temperature which are required in a thermal treatment. In order to solve the problems, the present invention provides a treating solution composed of an alcohol based solvent and a rare earth fluoride or alkaline earth metal fluoride dispersing in the solvent. In the treating solution, at least one X-ray diffraction peak has a half-value width larger than 1°. The present invention also provides a method for forming an insulating film using the treating solution.

Abstract: A magnet which includes ferromagnetic powder to be mainly a mother phase containing iron or cobalt. The ferromagnetic powder is provided with a high-resistance layer which has a resistance higher than or equal to ten times as high as a resistance of the mother phase and a Vickers hardness lower than a Vickers hardness of the mother phase. The high-resistance layer is being formed partially or entirely on the surface of the ferromagnetic powder.

Abstract: A permanent magnet comprises a hard magnetic material that contains at least a rare earth element and an anti-ferromagnetic material, wherein the hard magnetic material and the anti-ferromagnetic material are magnetically coupled. A volume ratio of the anti-ferromagnetic material is 20% or less, based on the permanent magnet.

Abstract: A magnet comprising magnetic powder containing at least one rare earth metal element, and an oxide binder for binding the magnetic powder, wherein an inter-face distance of the binder determined by diffraction analysis is 0.25 to 2.94 nm. The disclosure also discloses a method of manufacturing a magnet comprising; compacting magnetic powder containing at least one rare earth element under pressure in a mold; impregnating the compacted magnetic powder molding with a precursor solution of an oxide material; and heat-treating the compacted magnetic molding impregnated with the precursor thereby to impart an inter-face distance determined by diffraction analysis to the binder in the compacted molding. The distance is 0.25 to 2.94 nm.

Abstract: A compacted magnetic core with a high resistance, which comprises compacted magnetic powder of an iron powder or an alloy powder containing iron as a main ingredient and a layer of a rare earth metal fluoride or an alkaline earth metal fluoride on the surface of the powder, wherein the rare earth metal fluoride or the alkaline earth metal fluoride contains fluorine-depleted crystal lattice at a rate of 10% or less.

Abstract: A fluoride coating film formed with a fluoride-containing solution wherein a rare earth fluoride or an alkaline earth metal fluoride, in particular, fluoride of Pr, Nd, Dy, Tb and Ho, is swollen in a solvent comprising a major amount of an alcohol, and the solution is a colloidal solution in which the rare earth fluoride or the alkaline earth metal fluoride is dispersed homogeneously in the solvent comprising a major amount of an alcohol improves magnetic properties of NdFeB rare earth magnets including not only sintered magnets but also bonded magnets.

Abstract: Eddy current generated around a magnetic circuit in an MRI apparatus is one of the causes of deviation from an ideal magnetic field gradient waveform and causes image distortion, loss of strength, ghost generation, loss of signal, and spectral distortion. An object of the present invention is to suppress the generation of the eddy current. In an MRI apparatus, a ferromagnetic material formed from powder is used in a part of a magnetic circuit: the powder mainly comprising a mother phase containing iron or cobalt and showing ferromagnetism; and a high-resistance layer having a resistance not less than ten times as high as the mother phase and a Vickers hardness lower than that of the mother phase being formed in layers along parts of the surface of the powder on parts or the entire of the surface.

Abstract: A magnet comprising grains of a ferromagnetic material whose main component is iron and a fluorine compound layer or an oxy-fluorine compound layer of fluoride compound particles of alkali metals, alkaline earth metals and rare earth elements, present on the surface of the ferromagnetic material grains, wherein an amount of iron atoms in the fluorine compound particles is 1 to 50 atomic %.

Abstract: A magnetic powder according to the present invention comprises powder made of the iron element as a main component, and an insulator covering the surface of the powder. The powder has a spherical shape or a smoothed surface. The insulator comprises rare earth fluorides, alkaline metal fluorides, or alkaline earth metal fluorides. A soft magnetic composite formed by using this magnetic powder can suppress its eddy current loss in a wide frequency band and can also suppress its hysteresis loss due to compressed residual distortion in soft magnetic powder.

Abstract: The object of the present invention is to both reduce costs and improve magnetic characteristics of rare-earth bond magnets in which magnetic material is bound with a binding agent. In order to achieve this object, magnetic characteristics of a magnet are improved by performing cold forming on rare-earth magnetic powder by itself with no resin added. Then, in order to provide strength for the magnet, a low-viscosity SiO2 precursor is infiltrated and thermoset in the magnet shaped body. As a result, it is possible to obtain a rare-earth bond magnet in which magnetic characteristics are improved and costs are reduced.

Abstract: Eddy current generated around a magnetic circuit in an MRI apparatus is one of the causes of deviation from an ideal magnetic field gradient waveform and causes image distortion, loss of strength, ghost generation, loss of signal, and spectral distortion. An object of the present invention is to suppress the generation of the eddy current. In an MRI apparatus, a ferromagnetic material formed from powder is used in a part of a magnetic circuit: the powder mainly comprising a mother phase containing iron or cobalt and showing ferromagnetism; and a high-resistance layer having a resistance not less than ten times as high as the mother phase and a Vickers hardness lower than that of the mother phase being formed in layers along parts of the surface of the powder on parts or the entire of the surface.

Abstract: A lamellar high resistance layer having resistivity ten times or higher than that of a mother phase containing iron or cobalt is formed and an oxygen content is controlled to 10 to 10000 ppm so that the reliability and residual magnetic flux density are increased.

Abstract: A dynamoelectric machine comprising a stator having a plurality of slots and teeth, armature windings wound around the teeth, and a rotor disposed inside the stator, wherein a degauss alloy member is disposed in the inner periphery of the stator and the magnetic compensator has its surface or inside thereof a high resistance layer.

Abstract: It is an object to mold a high-resistance magnet at low temperature, including room temperature. The magnet comprises magnetic powders, non-ferrous metallic powders having a lower hardness than the magnetic powders and a high-resistance layer, wherein the magnetic powders occupy a larger volume than the metallic powders. In particular, the high-resistance layer contains a fluorine compound and is placed between the magnetic powder and non-ferrous metallic powders.