摘要:
A rare earth magnet having a composition represented by RTB wherein R denotes a rare earth element, T a transition metal and B boron, the magnet being composed of magnet powder constituted by crystalline particles. The particles of the magnetic powder have a ratio of a short diameter being 10 μm or more to a long diameter is 0.5 or less. An element Rm having a magnetic anisotropy higher than that of the rare earth element is contained in the surface and inside of the magnet constituted by the magnet powder in an approximately constant concentration. An oxy-fluoride and carbon are present at boundaries of the particles of the magnet powder.
摘要:
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.
摘要:
In a ferromagnetic material containing at least one kind of rare-earth element, a layer containing at least one kind of alkaline earth element or rare-earth element and fluorine is formed at the grain boundary or near the powder surface of the ferromagnetic material. A further layer containing at least one kind of rare-earth element, having a fluorine concentration lower than that of the layer described first and having a rare-earth element concentration higher than that of the host phase of the ferromagnetic material, or an oxide layer containing a rare-earth element is formed in adjacent with a portion of the layer described first.
摘要:
A sintered magnet according to the present invention is a sintered magnet configured from a magnetic powder grain having Nd2Fe14B as a main component, in which: fluorine, a heavy rare earth element, oxygen, and carbon are segregated in part of grain-boundary regions of said sintered magnetic powder grain; concentration of the carbon is higher than concentration of the fluorine at a grain-boundary triple junction of the grain-boundary region; and concentration of the heavy rare earth element decreases from said grain-boundary triple junction toward an inside of said magnetic powder grain.
摘要:
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 %.
摘要:
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 an 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.
摘要:
The object of the present invention is to provide a rare earth magnet which enables to achieve a good balance between high coercive force and high residual magnetic flux density, and its manufacturing method. The present invention provides a rare earth magnet in which a layered grain boundary phase is formed on a surface or a potion of a grain boundary of Nd2Fe14B which is a main phase of an R—Fe—B (R is a rare-earth element) based magnet, and wherein the grain boundary phase contains a fluoride compound, and wherein a thickness of the fluoride compound is 10 μm or less, or a thickness of the fluoride compound is from 0.1 μm to 10 μm, and wherein the coverage of the fluoride compound over a main phase particle is 50% or more on average. Moreover, after layering fluoride compound powder, which is formed in plate-like shape, in the grain boundary phase, the rare earth magnet is manufactured by quenching the layered compound after melting it at a vacuum atmosphere at a predetermined temperature, or by heating and pressing the main phase and the fluoride compound to make the fluoride compound into a layered fluoride compound along the grain boundary phase.
摘要:
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.
摘要:
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.
摘要:
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.