摘要:
Disclosed is a method for the preparation of a novel composite rare earth-based magnetically anisotropic sintered permanent magnet in which: (a) a base alloy consisting of a host phase of R.sub.2 T.sub.14 B (R: a rare earth element; T: iron or a combination of iron and cobalt) having a particle diameter of 2 to 10 .mu.m and containing in each particle a phase rich in the content of T and having a particle diameter not exceeding 1 .mu.m is prepared by the strip casting method; (b) the base alloy is crushed; (c) the base alloy powder is blended in a specified proportion with a powder of an auxiliary alloy of R-T or R-T-B in a specified proportion; (d) the powder blend is subjected to further comminution; (e) the comminuted powder blend is subjected to compression-molding in a magnetic field into a powder compact; and (f) the powder compact is sintered by a heat treatment.
摘要:
Disclosed is a rare earth-based, magnetically anisotropic permanent magnet material consisting of a rare earth element, e.g., neodymium or praseodymium, iron optional in combination with cobalt and boron and having excellent magnetic properties by virtue of the magnetic coupling between the magnetically hard and soft phases. The magnet material has a structure consisting of crystalline particles of, e.g., Nd.sub.2 Fe.sub.14 B, having a particle diameter of 1 .mu.m or larger and fine crystals of iron of submicron size in a rod-shaped or platelet form precipitated within each crystalline particle of Nd.sub.2 Fe.sub.14 B. This magnet material can be prepared by several different methods including, for example, a solid phase reaction of an intermetallic compound of Nd.sub.2 Fe.sub.17 with boron to effect a double decomposition reaction producing Nd.sub.2 Fe.sub.14 B and iron.
摘要翻译:公开了一种稀土类磁性各向异性永磁材料,其由稀土元素(例如钕或镨)组成,铁与钴和硼组合可选,并且由于磁性硬和 软相。 磁体材料具有由例如粒径为1μm以上的Nd 2 Fe 14 B的结晶粒子构成的结构,在Nd 2 Fe 14 B的各结晶粒子内析出棒状或者血小板形状的亚微米尺寸的铁的微细结晶。 该磁体材料可以通过几种不同的方法制备,包括例如Nd 2 Fe 17的金属间化合物与硼的固相反应,以产生产生Nd 2 Fe 14 B和铁的双重分解反应。
摘要:
Provided by the invention is a method for the preparation of a magnetically anisotropic permanent magnet mainly consisting of crystallites of the Nd.sub.2 Fe.sub.14 B phase. The method comprises the steps of:(a) preparing an amorphous alloy of neodymium, iron and boron in molar fractions corresponding to the Nd.sub.2 Fe.sub.14 B phase or a nanocomposite of the Nd.sub.2 Fe.sub.14 B/Fe.sub.3 B or Nd.sub.2 Fe.sub.14 B/Fe system, for example, by the melt-spun method; and (b) subjecting the amorphous alloy of neodymium, iron and boron to a heat treatment in a magnetic field of at least 3 T (tesla) at a temperature in the range from 550 to 800.degree. C. for a length of time in the range from 1.times.10.sup.2 to 1.times.10.sup.4 seconds in an atmosphere of a non-reactive gas or vacuum.
摘要翻译:本发明提供了一种主要由Nd2Fe14B相微晶组成的磁各向异性永磁体的制备方法。 该方法包括以下步骤:(a)制备与Nd 2 Fe 14 B相对应的摩尔分数的钕,铁和硼的非晶合金,或者通过熔融纺丝制备Nd 2 Fe 14 B / Fe 3 B或Nd 2 Fe 14 B / Fe体系的纳米复合材料 方法; 和(b)使钕,铁和硼的非晶合金在至少3T(特斯拉)的磁场中在550-800℃的温度下进行热处理一段时间 在非反应性气体或真空气氛中,范围为1×102-1×104秒。
摘要:
A method of producing a SiC single crystal includes: disposing a SiC seed crystal at a bottom part inside a graphite crucible; causing a solution containing Si, C and R (R is at least one selected from the rare earth elements inclusive of Sc and Y) or X (X is at least one selected from the group consisting of Al, Ge, Sn, and transition metals exclusive of Sc and Y) to be present in the crucible; supercooling the solution so as to cause the SiC single crystal to grow on the seed crystal; and adding powdery or granular Si and/or SiC raw material to the solution from above the graphite crucible while keeping the growth of the SiC single crystal.
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:
An R—Fe—B base sintered magnet having a composition of 12–17 at % of R (wherein R stands for at least two of yttrium and rare earth elements and essentially contains Nd and Pr), 0.1–3 at % of Si, 5–5.9 at % of B, 0–10 at % of Co, and the balance of Fe, containing a R2(Fe,(Co),Si)14B intermetallic compound primary phase and at least 1% by volume of an R—Fe(Co)—Si grain boundary phase, and being free of a B-rich phase exhibits a coercive force of at least 10 kOe despite a reduced content of heavy rare earth.
摘要:
A rare earth magnet is prepared by disposing a R1-T-B sintered body comprising a R12T14B compound as a major phase in contact with an R2-M alloy powder and effecting heat treatment for causing R2 element to diffuse into the sintered body. The alloy powder is obtained by quenching a melt containing R2 and M. R1 and R2 are rare earth elements, T is Fe and/or Co, M is selected from B, C, P, Al, Si, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, Zr, Nb, Mo, Ag, In, Sn, Sb, Hf, Ta, W, Pt, Au, Pb, and Bi.
摘要:
A method of producing a SiC single crystal includes: disposing a SiC seed crystal at a bottom part inside a graphite crucible; causing a solution containing Si, C and R (R is at least one selected from the rare earth elements inclusive of Sc and Y) or X (X is at least one selected from the group consisting of Al, Ge, Sn, and transition metals exclusive of Sc and Y) to be present in the crucible; supercooling the solution so as to cause the SiC single crystal to grow on the seed crystal; and adding powdery or granular Si and/or SiC raw material to the solution from above the graphite crucible while keeping the growth of the SiC single crystal.
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 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.