摘要:
Phosphor particles are provided in the form of spherical polycrystalline secondary particles consisting of a multiplicity of primary particles, including a garnet phase having the compositional formula: (A1-xBx)3C5O12 wherein A is Y, Gd, and/or Lu, B is Ce, Nd, and/or Tb, C is Al and/or Ga, and 0.002≦x≦0.2, the secondary particles having an average particle size of 5-50 μm.
摘要:
A rare earth permanent magnet is prepared by disposing a powdered metal alloy containing at least 70 vol % of an intermetallic compound phase on a sintered body of R—Fe—B system, and heating the sintered body having the powder disposed on its surface below the sintering temperature of the sintered body in vacuum or in an inert gas for diffusion treatment. The advantages include efficient productivity, excellent magnetic performance, a minimal or zero amount of Tb or Dy used, an increased coercive force, and a minimized decline of remanence.
摘要:
A permanent magnet material is prepared by machining an anisotropic sintered magnet body having the compositional formula: Rx(Fe1-yCoy)100-x-z-aBzMa wherein R is Sc, Y or a rare earth element, M is Al, Cu or the like, to a specific surface area of at least 6 mm−1, heat treating in a hydrogen gas-containing atmosphere at 600-1,100° C. for inducing disproportionation reaction on the R2Fe14B compound, and continuing heat treatment at a reduced hydrogen gas partial pressure and 600-1,100° C. for inducing recombination reaction to the R2Fe14B compound, thereby finely dividing the R2Fe14B compound phase to a crystal grain size ≦1 μm.
摘要:
A rare earth permanent magnet is prepared by disposing a powdered metal alloy containing at least 70 vol % of an intermetallic compound phase on a sintered body of R—Fe—B system, and heating the sintered body having the powder disposed on its surface below the sintering temperature of the sintered body in vacuum or in an inert gas for diffusion treatment. The advantages include efficient productivity, excellent magnetic performance, a minimal or zero amount of Tb or Dy used, an increased coercive force, and a minimized decline of remanence.
摘要:
A rare-earth alloy ingot is produced by melting an alloy composed of 20-30 wt % of a rare-earth constituent which is Sm alone or at least 50 wt % Sm in combination with at least one other rare-earth element, 10-45 wt % of Fe, 1-10 wt % of Cu and 0.5-5 wt % of Zr, with the balance being Co, and quenching the molten alloy in a strip casting process. The strip-cast alloy ingot has a content of 1-200 μm size equiaxed crystal grains of at least 20 vol % and a thickness of 0.05-3 mm. Rare-earth sintered magnets made from such alloys exhibit excellent magnetic properties and can be manufactured under a broad optimal temperature range during sintering and solution treatment.
摘要:
A method for preparing a rare earth permanent magnet material is characterized by comprising the steps of disposing a powder mixture on a surface of a sintered magnet body of R1—Fe—B composition wherein R1 is at least one element selected from rare earth elements inclusive of Sc and Y, the powder mixture comprising a powder containing at least 0.5% by weight of M which is at least one element selected from Al, Cu, and Zn and having an average particle size equal to or less than 300 μm and a powder containing at least 30% by weight of a fluoride of R2 which is at least one element selected from rare earth elements inclusive of Sc and Y and having an average particle size equal to or less than 100 μm, and heat treating the magnet body having the powder disposed on its surface at a temperature equal to or below the sintering temperature of the magnet body in vacuum or in an inert gas, for causing at least one of M and R2 in the powder mixture to be absorbed in the magnet body. The invention provides an R—Fe—B sintered magnet with high performance and a minimized amount of Tb or Dy used.
摘要:
A rare earth permanent magnet is prepared from a sintered magnet body of a R1—Fe—B composition wherein R1 is a rare earth element inclusive of Y and Sc, by forming a plurality of slits in a surface of the magnet body, disposing a powder on the magnet body surface, the powder comprising an oxide of R2, a fluoride of R3, or an oxyfluoride of R4 wherein each of R2, R3, and R4 is a rare earth element, and heat treating the magnet body and the powder below the sintering temperature in vacuum or in an inert gas.
摘要:
A method for preparing a rare earth permanent magnet material comprises the steps of disposing a powder on a surface of a sintered magnet body of R1aTbAcMd composition wherein R1 is a rare earth element inclusive of Sc and Y, T is Fe and/or Co, A is boron (B) and/or carbon (C), M is Al, Cu, Zn, In, Si, P, S, Ti, V, Cr, Mn, Ni, Ga, Ge, Zr, Nb, Mo, Pd, Ag, Cd, Sn, Sb, Hf, Ta, or W, said powder comprising an oxide of R2, a fluoride of R3 or an oxyfluoride of R4 wherein R2, R3, and R4 are rare earth elements inclusive of Sc and Y and having an average particle size equal to or less than 100 μm, heat treating the magnet body and the powder at a temperature equal to or below the sintering temperature of the magnet body for absorption treatment for causing R2, R3, and R4 in the powder to be absorbed in the magnet body, and repeating the absorption treatment at least two times. According to the invention, a rare earth permanent magnet material can be prepared as an R—Fe—B sintered magnet with high performance and a minimized amount of Tb or Dy used.
摘要:
Hydrogen embrittlement is prevented in Sm2Co17-based magnets and R2Fe14B-based magnets by metal plating the magnet, then carrying out heat treatment, or by forming a metal oxide or metal nitride layer on the metal plating layer or directly on the magnet itself.
摘要翻译:基于Sm 2 N 2基的磁体和R 2 Fe 14 B基磁体可防止氢脆化, 金属电镀磁体,然后进行热处理,或者通过在金属镀层上形成金属氧化物或金属氮化物层,或者直接在磁体本身上形成金属氧化物或金属氮化物层。
摘要:
A rare earth permanent magnet material is prepared by covering a sintered magnet body of R1—Fe—B composition wherein R1 is a rare earth element, with a powder comprising at least 30% by weight of an alloy of R2aTbMcAdHe wherein R2 is a rare earth element, T is Fe and/or Co, and M is Al, Cu or the like, and having an average particle size up to 100 μm, and heat treating the powder-covered magnet body at a suitable temperature, for causing R2, T, M and A in the powder to be absorbed in the magnet body.