摘要:
The objects of the present invention are to provide a method of producing highly weather-resistant iron-based magnet powder containing a rare-earth element, particularly characterized by high coercive force in a practically important humid atmosphere, highly weather-resistant magnet powder produced by the same method, resin composition containing the same powder for bonded magnets, and bonded magnet containing the same powder. The present invention provides a method of producing a magnet powder by crushing an iron-based magnet powder containing a rare-earth element in an organic solvent, wherein phosphoric acid is added to the solvent in which the powder is crushed.
摘要:
Magnetic acicular alloy particles containing iron as a main component according to the present invention, have an average major axial diameter of 0.05 to 0.2 &mgr;m, and pH values of water suspensions of said magnetic acicular alloy particles containing iron as a main component, which satisfies the formula: (pH value of water suspension treated by A method)−(pH value of water suspension treated by B method)
摘要:
A process is disclosed for producing rare earth-iron-boron alloys and magnets with reduced oxygen content and improved yield. Such a reduction in oxygen content and improvement in yield are achieved by including copper in a melt having a composition comprising a rare earth, boron, and iron, and subsequently solidifying the melt.
摘要:
This invention relates to the formula and preparation method for a multi-layer chip inductor material used in very high frequencies. The main composition of this material is planar hexagonal soft magnetic ferrite, and ingredient is low temperature sintering aid. Preparation method is a synthetic method of solid phase reaction. The sintering aid is prepared by secondary doping. By the process of ball grinding, drying, pre-calcining, ball grinding, drying, granulating, forming, sintering, and so forth, very high frequency inductor material of superior quality is obtained, realizing low temperature sintering under a temperature lower than 900° C. This invention is of low cost, high performance, suitable for multi-layer chip inductors at very high frequencies of 300M-800 MHz.
摘要:
A ferromagnetic powder comprising ferromagnetic particles coated with a material that does not degrade at temperatures above 150° C. and permits adjacent particles to strongly bind together after compaction such that parts made from the ferromagnetic powder have a transverse rupture strength of about 8,000 to about 20,000 pounds/square inch before sintering, The coating includes from 2 to 4 parts of an oxide and one part of a chromate, molybdate, oxalate, phosphate, or tungstate. The coating may be substantially free of organic materials. The invention also includes a method of making the ferromagnetic powder, a method of making soft magnetic parts from the ferromagnetic powder, and soft magnetic parts made from the ferromagnetic powder.
摘要:
An R—Fe—B permanent magnet wherein R is Nd or a combination of Nd with a rare earth element is prepared by casting an R—Fe—B alloy, crushing the alloy in an oxygen-free atmosphere of argon, nitrogen or vacuum, effecting comminution, compaction, sintering, aging, and cutting and/or polishing the magnet to give a finished surface. The magnet is then heat treated in an argon, nitrogen or low-pressure vacuum atmosphere having a limited oxygen partial pressure, obtaining a highly oil resistant sintered permanent magnet having corrosion resistance and hydrogen barrier property even in a high pressure hot environment of refrigerant and/or lubricant as encountered in compressors.
摘要:
A method and apparatus for manufacturing a rare earth magnet is disclosed. In a first step, a compact is produced by compacting rare earth alloy powder in a predetermined space in an orienting magnetic field. Next, a demagnetizing process is performed for the compact, and the compact is ejected from the predetermined space. Then, a additional demagnetizing process is performed for magnetic powder adhering to a surface of the compact by applying an magnetic field to the compact after the compact is ejected.
摘要:
The invention concerns a process for the preparation of soft magnetic composite products comprising the steps of providing particles of an iron based soft magnetic material with an electrically insulating layer; optionally mixing the dry powder with a lubricant; compacting the powder and heating the obtained component at an elevated temperature in the presence of water vapour. The invention also comprises the iron powder compact subjected to this treatment.
摘要:
A method of a manufacturing rotating electromagnetic component to have both soft and hard (permanent) magnet regions, in which powder technologies are used to net-shape mold the component. A soft magnet powder material and an insert or powder of a permanent magnet material are compacted to form a rotating electromagnetic body containing soft and hard magnet regions. A partial sintering operation is then performed on the body at a temperature of 1600° F. (about 870° C.) or less, preferably about 1400° F. to 1500° F. (about 760° C. and 830° C.), and most preferably at 1500° F. to at least partially fuse the soft magnet powder materials with the permanent magnet material. The soft powder component of the resulting electromagnetic body is sufficiently fused to exhibit mechanical properties comparable to a fully sintered body (i.e., sintered at 2050° F. (about 1120° C.) or more), but without degrading the magnetic properties of the hard magnet region.