摘要:
The present invention discloses rare earth-bonded magnetic powder and a preparation method therefor. The bonded magnetic powder is of a multilayer core-shell structure, and comprises a core layer and an antioxidant layer (3), wherein the core layer is formed by RFeMB, R is Nd and/or PrNd, and M is one or more of Co, Nb, and Zr; and the core layer is coated with an iron-nitrogen layer (2). In addition, the present invention also discloses the preparation method for the rare earth-bonded magnetic powder and a bonded magnet. The oxidation and corrosion of magnetic raw powder during phosphorization and subsequent treatment process are effectively prevented, thereby further improving the long-term temperature resistance and environmental tolerance of the material.
摘要:
The present invention discloses an yttrium-added rare earth permanent magnet material and a preparation method therefor. The chemical formula of the material is expressed as (YxRe1-x)aFe100-a-b-cMbBc according to the mass percentage, wherein 0.05≤x≤0.5, 20≤a≤28, 0.5≤b≤2, 0.5≤c≤1.5, Re is Nd and/or Pr, and M is Al and/or Nb. According to the present invention, the relatively surplus and inexpensive rare earths yttrium and cerium are used to replace Nd and/or Pr in NdFeB. By controlling the ratio of the rare earth elements such as yttrium, cerium and neodymium, and adding an appropriate amount of Nb and/or Al element, the rare earth elements are used in a comprehensive and balanced manner while better magnetic properties are maintained.
摘要:
A method for preparing a rare earth anisotropic bonded magnetic powder, comprises the following steps: (1) preparing raw powder with RTBH as the main component, wherein, R is Nd or Pr/Nd, and T is a transition metal containing Fe; (2) adding La hydride or Ce hydride and copper powder to the raw powder to form a mixture; (3) subjecting the mixture to atmosphere diffusion heat treatment to give the rare earth anisotropic bonded magnetic powder.
摘要:
Provided are a highly thermostable rare-earth permanent magnetic material, a preparation method thereof and a magnet containing the same. A composition of the rare-earth permanent magnetic material by an atomic percentage is as follows: SMxRaFe100-x-y-z-aMyNz, wherein R is at least one of Zr and Hf, M is at least one of Co, Ti, Nb, Cr, V, Mo, Si, Ga, Ni, Mn and Al, x+a is 7-10%, a is 0-1.5%, y is 0-5% and z is 10-14%.
摘要:
The application discloses a rare-earth permanent magnetic powder, a bonded magnet, and a device using the bonded magnet. The rare-earth permanent magnetic powder comprises 4 to 12 at. % of Nd, 0.1 to 2 at. % of C, 10 to 25 at. % of N and 62.2 to 85.9 at. % of T, wherein T is Fe or FeCo and the main phase of the rare-earth permanent magnetic powder is a hard magnetic phase with a TbCu7 structure. Material volatilization can be avoided effectively during a preparation process of the rare earth permanent magnetic powder, thus improving the wettability with a water-cooling roller during the preparation process and final prepared materials are provided with good magnetic properties.
摘要:
The present disclosure discloses an yttrium (Y)-added rare-earth permanent magnetic material and a preparation method thereof. A chemical formula of the material expressed in atomic percentage is (YxRE1-x)aFebalMbNc, wherein 0.05≤x≤0.4, 7≤a≤13, 0≤b≤3, 5≤c≤20, and the balance is Fe, namely, bal=100-a-b-c; RE represents a rare-earth element Sm, or a combination of the rare-earth element Sm and any one or more elements of Zr, Nd and Pr; M represents Co and/or Nb; and N represents nitrogen. In the preparation method, the rare-earth element Y is utilized to replace the element Sm of a samarium-iron-nitrogen material. By regulating a ratio of the element Sm to the element Y, viscosity of an alloy liquid can be reduced, and an amorphous forming ability of the material is enhanced.
摘要:
The invention discloses a composite rare earth anisotropic bonded magnet and a preparation method thereof. The composite rare earth anisotropic bonded magnet comprises a Nd—Fe—B magnetic powder, a Sm—Fe—N magnetic powder, a binder and an inorganic nano-dispersant. The preparation method comprises steps of preparing a Nd—Fe—B magnetic powder by a HDDR method, preparing a Sm—Fe—N magnetic powder by a powder metallurgy method, mixing the Nd—Fe—B magnetic powder, the Sm—Fe—N magnetic powder, the binder and the inorganic nano-dispersant at a specific ratio to finally obtain the composite rare earth anisotropic bonded magnet. The invention, by adding an inorganic nano-dispersant, enables the full dispersion of the fine Sm—Fe—N powder during the mixing process of the binder, the Nd—Fe—B magnetic powder and the Sm—Fe—N powder, and thus makes the fine Sm—Fe—N powder and the binder evenly coated on the surface of the anisotropic Nd—Fe—B magnetic powder.
摘要:
An anisotropic bonded magnet and a preparation method thereof are provided. By stacking magnets having different magnetic properties and/or densities, the magnets in the middle have high properties and the magnets at two ends and/or the periphery have low properties, thereby compensating for a property deviation caused by a difference in pressing densities during a pressing process, and improving the property uniformity of the magnets in an axial direction. The method solves the problem of “low in the middle and high at two ends” caused by the phenomenon of non-uniform magnetic field orientation and density along a height direction during orientation and densification.
摘要:
The invention discloses an anisotropic bonded magnetic powder and a preparation method thereof. The anisotropic bonded magnetic powder has a general formula of R1R2TB, wherein R1 is a rare earth element containing Nd or PrNd, R2 is one or two of La and Ce, T is a transitional element, and B is boron. The preparation method includes the steps of smelting the master alloy to prepare ingot(s), preparing a rare earth hydride of formula R1TBHX, preparing a hydride diffusion source of formula R1R2THX, mixing, heat treating, and high-vacuum dehydrogenating, to obtain the anisotropic bonded magnetic powder. The invention uses La and Ce hydrides as the diffusion source, can save cost, remove hydrogen from the diffusion source at a lower dehydrogenation temperature, avoid crystal grain growth at a high temperature, and ensure the quality of the product.
摘要:
The present invention relates to an R-T-B sintered magnet and a preparation method thereof. The sintered magnet includes a grain boundary region T1, a shell layer region T2 and an R2Fe14B grain region T3; at 10 μm to 60 μm from a surface of the sintered magnet toward a center thereof, an area ratio of the shell layer region T2 to the R2Fe14B grain region T3 is 0.1 to 0.3, and a thickness of the shell layer region T2 is 0.5 μm to 1.2 μm; and an average coating percent of the shell layer region T2 on the R2Fe14B grain region T3 is 80% or more. In the present invention, by optimizing a preparation process and a microstructure of a traditional rare earth permanent magnet, diffusion efficiency of heavy rare earth in the magnet is improved, such that coercivity of the magnet is greatly improved, and manufacturing cost is reduced.