H01F1/0557

R-T-B BASED PERMANENT MAGNET MATERIAL AND METHOD FOR PREPARING THE SAME
20230049109 · 2023-02-16 ·

The present invention relates to an R-T-B based permanent magnet material, having a composition of R.sub.xT.sub.yTm.sub.qB.sub.z (at. %), wherein 13≤x≤15.5, 0.5≤q≤3, 0.85≤z≤1, y=100−x−q−z; wherein R is LR.sub.aHR.sub.1-a, LR is one selected from the group consisting of Pr, Nd, PrNd, or a combination thereof, HR is one selected from the group consisting of Dy and Tb, or a combination thereof, and 0.95≤a≤1; wherein T is one selected from the group consisting of Fe and Co, or a combination thereof; and Tm is a transition metal. The advantage of the method is that: plating a heavy rare earth film on alloy flakes using a magnetron sputtering device, and the coercivity of the magnet is significantly increased simply by having a “core-shell” structure without long time diffusion heat treatment.

Real-time methods for magnetic resonance spectra acquisition

The invention pertains to advances in real-time methods in nuclear magnetic resonance by offering a new dual-frequency dynamic nuclear polarization (DNP) method that uses a microwave beam to polarize the spins of electrons and concomitantly act as a NMR transmitter.

CASTER ASSEMBLY

A caster assembly configured to process and store a material includes a reaction chamber, a storage assembly configured to store material processed in the reaction chamber, and a blower configured to process and store the material. The reaction chamber includes a vessel configured to hold the material in a melted state prior to processing and a powder generating assembly configured to receive the material from the melting vessel. The powder generating assembly includes a feeding chamber and a feeding device disposed at least partially within the feeding chamber. The feeding device includes at least one nozzle configured to inject inert fluid, where the fluid is a gas, liquid, or combination of the two into the feeding chamber and a material inlet through which the material is configured to flow into the feeding chamber to be exposed to the inert fluid, where the fluid is a gas, liquid, or combination of the two.

Samarium-cobalt magnets and method for preparing the same

The present invention provides a samarium-cobalt magnet and a method for preparing the same. The method comprises mixing an alloy powder with a zirconium powder in an amount of 0.1-0.35 wt % of the weight of the alloy powder to form a mixture. The alloy powder is formed from 10.5-13.5 wt % of samarium, 12.5-15.5 wt % gadolinium, 50-55 wt % of cobalt, 13-17 wt % of iron, 4-10 wt % of copper, and 2-7 wt % of zirconium. The method brings about at low costs a samarium-cobalt magnet having a positive temperature coefficient of remanence.

HIGH-RESISTIVITY SINTERED SAMARIUM-COBALT MAGNET AND PREPARATION METHOD THEREOF

The present invention discloses a high-resistivity sintered samarium-cobalt magnet and a preparation method thereof. According to the present invention, considering the specialty of sintered samarium-cobalt magnetic powder, fluoride or oxide is firstly prepared into nano-powder using high-energy ball milling, and the samarium-cobalt magnetic powder is prepared separately by rolling ball milling or high-speed jet milling, and then a certain electric field is applied in a fluoride suspension to drive the fluoride nano-powder to evenly cover a surface of the samarium-cobalt magnetic powder. The present invention breaks through the technical bottleneck that fluoride/oxide can improve the resistivity of a samarium-cobalt magnet but result in deterioration of the magnetic properties.

ANISOTROPIC RARE EARTH SINTERED MAGNET AND METHOD FOR PRODUCING THE SAME

Provided are an anisotropic rare earth sintered magnet having a ThMn.sub.12-type crystal compound as a main phase and exhibits good magnetic characteristics, and a method for producing it. The anisotropic rare earth sintered magnet has a composition of a formula (R.sub.1-aZr.sub.a).sub.v(Fe.sub.1-bCo.sub.b).sub.100-v-w-x-y(M.sup.1.sub.1-cM.sup.2.sub.c).sub.wO.sub.xC.sub.y (where R is one or more kinds selected from rare earth elements and indispensably includes Sm, M.sup.1 is one or more kinds of elements selected from the group consisting of V, Cr, Mn, Ni, Cu, Zn, Ga, Al, and Si, M.sup.2 is one or more kinds of elements selected from the group consisting of Ti, Nb, Mo, Hf, Ta, and W, and v, w, x, y, a, b, and c each satisfy 7≤v≤15 at %, 4≤w≤20 at %, 0.2≤x≤4 at %, 0.2≤y≤2 at %, 0≤a≤0.2, 0≤b≤0.5, and 0≤c≤0.9), which contains a main phase of a ThMn.sub.12-type crystal compound in an amount of 80% by volume or more with the average crystal particle diameter of the main phase being 1 μm or more, which contains an R oxycarbide in the grain boundary area, and which has a density of 7.3 g/cm.sup.3 or more. The production method for the anisotropic rare earth sintered magnet includes grinding an alloy that contains a ThMn.sub.12-type crystal compound phase but does not contain an oxycarbide, then molding it in a mode of pressure powder molding with magnetic field application thereto to give a molded article, and thereafter sintering it at a temperature of 800° C. or higher and 1400° C. or lower to form an oxycarbide in the grain boundary area.

PERMANENT MAGNET AND DEVICE
20230095210 · 2023-03-30 ·

A permanent magnet having excellent magnetic properties, and a device including such a permanent magnet are provided. A permanent magnet consists of a sintered compact having a composition consisting of, in a mass percentage composition, R: 23 to 27% (R is a rare-earth element including at least Sm); Fe: 22 to 27%; Mn: 0.01 to 2.5%; and a remainder consisting of Co and unavoidable impurities, in which the sintered compact contains a plurality of crystal grains and grain boundaries, an average crystal grain size (A. G.) of the crystal grains is equal to or larger than 100 μm, and a coefficient of variation (C. V.) of crystal grain sizes is equal to or smaller than 0.60.

Caster assembly

A caster assembly configured to process and store a material includes a reaction chamber, a storage assembly configured to store material processed in the reaction chamber, and a blower configured to process and store the material. The reaction chamber includes a vessel configured to hold the material in a melted state prior to processing and a powder generating assembly configured to receive the material from the melting vessel. The powder generating assembly includes a feeding chamber and a feeding device disposed at least partially within the feeding chamber. The feeding device includes at least one nozzle configured to inject inert fluid, where the fluid is a gas, liquid, or combination of the two into the feeding chamber and a material inlet through which the material is configured to flow into the feeding chamber to be exposed to the inert fluid, where the fluid is a gas, liquid, or combination of the two.

METHOD FOR IMPROVING MAGNETIC PROPERTIES OF CERIUM-YTTRIUM-RICH RARE EARTH PERMANENT MAGNET
20220344081 · 2022-10-27 ·

A method for improving magnetic properties of a Ce—Y-rich rare earth permanent magnet is provided, and the Ce—Y-rich rare earth permanent magnet is subjected to pressurized heat treatment to improve magnetic properties. The method includes: preparing a pristine magnet through a sintering process; and placing the pristine magnet into a pressurized heat treatment device and performing pressurized heat treatment under the protection of an argon atmosphere. By regulating parameters such as pressure, temperature and holding time in the heat treatment process, element diffusion in the Ce—Y-rich permanent magnet is promoted, and coercivity, remanence, magnetic energy product and temperature stability of the Ce—Y-rich permanent magnet are improved. The method has advantages of a simple process with low energy consumption, a substitution amount of rare earths Ce—Y up to 90 wt % while having excellent magnetic performance, so that a way for efficient utilization of high-abundance rare earths Ce and Y is provided.

Rare earth permanent magnets and their preparation

A sintered magnet body (R.sub.aT.sup.1.sub.bM.sub.cB.sub.d) coated with a powder mixture of an intermetallic compound (R.sup.1.sub.iM.sup.1.sub.j, R.sup.1.sub.xT.sup.2.sub.yM.sup.1.sub.z, R.sup.1.sub.iM.sup.1.sub.jH.sub.k), alloy (M.sup.1.sub.dM.sup.2.sub.e) or metal (M.sup.1) powder and a rare earth (R.sup.2) oxide is diffusion treated. The R.sup.2 oxide is partially reduced during the diffusion treatment, so a significant amount of R.sup.2 can be introduced near interfaces of primary phase grains within the magnet through the passages in the form of grain boundaries. The coercive force is increased while minimizing a decline of remanence.