Provided is a sintered magnet that is an R-T-B based sintered magnet having a region having a concentration of at least one heavy rare earth element decreasing from the surface toward the inside, in which the at least one heavy rare earth element includes at least either of Tb or Dy, R includes Nd, T includes Fe, Co, and Cu, there is a grain boundary phase containing at least either of Tb or Dy and Nd between two main phase particles, and a value obtained by subtracting a half value width of a concentration distribution curve of Cu from a half value width of a concentration distribution curve of Tb or Dy in a part including the grain boundary phase is from 10 to 20 nm.

The present invention relates to a method for preparing a neodymium-iron-boron rare-earth permanent magnetic material, in particular to a hot press molding-based method for preparing a rare-earth permanent magnet. The problem that the residual magnetism and coercive force of a rare-earth permanent magnet prepared in the prior art cannot be both high is solved. An RTM alloy infiltrates same during an HD treatment. RTM sticks to the surface of coarse powder and infiltrates into the interior of the coarse powder along a grain boundary. The temperature of hot press sintering is relatively low, and grains barely grow. In the absence of Dy and Tb, a higher coercive force is obtained. If an alloy containing Dy and Tb is used for infiltration, these atoms diffuse into the surface layer of a main phase during preheating and heat treatment, achieving grain boundary hardening. Under the premise of a very small reduction in the residual magnetism, the coercive force is greatly improved.

A rare earth permanent magnet material and a raw Material composition, a preparation method therefor and use thereof. The rare earth permanent magnet material comprises the following components in percentage by mass: 29.0-32.0 wt. % of R. where R comprises RH, and the content of RH is greater than 1 wt. %; 0.30-0.50 wt. % of Cu (not including 0.50 wt. %); 0.10-1.0 wt. % of Co; 0.05-0.20 wt. % of Ti; 0.92-0.98 wt. % of 13; and the remainder being Fe and unavoidable impurities; wherein R is a rare-earth element and at least comprises Nd; and RH is a heavy rare-earth element and at least comprises Tb. The R-T-B system permanent magnet material exhibits excellent performance, wherein Br≥14.30 kGs, and Hej≥24.1 kOe. The invention can synchronously improve Br and Hcj.

A rare earth permanent magnet material and a raw Material composition, a preparation method therefor and use thereof. The rare earth permanent magnet material comprises the following components in percentage by mass: 29.0-32.0 wt. % of R. where R comprises RH, and the content of RH is greater than 1 wt. %; 0.30-0.50 wt. % of Cu (not including 0.50 wt. %); 0.10-1.0 wt. % of Co; 0.05-0.20 wt. % of Ti; 0.92-0.98 wt. % of 13; and the remainder being Fe and unavoidable impurities; wherein R is a rare-earth element and at least comprises Nd; and RH is a heavy rare-earth element and at least comprises Tb. The R-T-B system permanent magnet material exhibits excellent performance, wherein Br≥14.30 kGs, and Hej≥24.1 kOe. The invention can synchronously improve Br and Hcj.

A two-step diffusion method for preparing high-performance dual-main-phase sintered mischmetal-iron-boron magnet belongs to the preparing technical field of rare earth permanent magnet materials. The compositions of the two main phase alloys are RE-Fe—B (RE is Nd or Pr) and (Nd, MM)-Fe—B (MM is mischmetal), respectively. First, PrHoFe strip-casting alloy is used as a diffusion source. Next, a PrHo-rich layer is uniformly coated on the surface of (Nd, MM)-Fe—B hydrogen decrepitation powders. The higher anisotropic fields of Pr.sub.2Fe.sub.14B and Ho.sub.2Fe.sub.14B are used to improve the coercivity. Then, the ZrCu strip-casting alloy is used as a diffusion source. A Zr-rich layer is uniformly coated on the surface of the powders after the first-step diffusion, which prevents the growth of the MM-rich main phase grains during the sintering process and the inter-diffusion between the two main phases, thus obtaining high coercivity.

A preparation method of improved sintered neodymium-iron-boron (Nd—Fe—B) casting strips includes the following steps: firstly nucleation assisted alloy particles used for sintered Nd—Fe—B casting strips are prepared, all elements are weighted as follows: 26.68-28% of Pr—Nd, 70-72.5% of Fe and 0.90-1% of B, and a Pr element in two elements of Pr—Nd accounts for 0-30 wt %; the compounded materials are smelted and poured to obtain alloy strips, then the alloy strips are crushed into particles with diameter of 1-10 mm; secondly, Nd—Fe—B casting strips are prepared: the prepared intermediate materials are smelted and melted into molten steel, and then are refined; after the intermediate materials are fully melted, the nucleation assisted alloy particles are added; and after the nucleation assisted alloy particles are added, smelting is performed for 3-15 minutes pouring is performed, and final Nd—Fe—B alloy casting strips are obtained.

Disclosed herein are embodiments of systems and method for processing feedstock materials using microwave plasma processing. Specifically, the feedstock materials disclosed herein pertain to metal powders. Microwave plasma processing can be used to spheroidize the metal powders and form metal nitride or metal carbide powders. The stoichiometry of the metal nitride or metal carbide powders can be controlled by changing the composition of the plasma gas and the residence time of the feedstock materials during plasma processing.

Disclosed herein are embodiments of systems and method for processing feedstock materials using microwave plasma processing. Specifically, the feedstock materials disclosed herein pertain to metal powders. Microwave plasma processing can be used to spheroidize the metal powders and form metal nitride or metal carbide powders. The stoichiometry of the metal nitride or metal carbide powders can be controlled by changing the composition of the plasma gas and the residence time of the feedstock materials during plasma processing.

A method for preparing powders of hard alloys, such as Ti and Ti—Zr alloys, using a hydride-dehydride process, and powders produced by the process, are disclosed. The method can be used to manufacture brazing powders. The method is less hazardous and more cost effective than current methods, such as gas atomization, of preparing such braze materials.

A method for preparing powders of hard alloys, such as Ti and Ti—Zr alloys, using a hydride-dehydride process, and powders produced by the process, are disclosed. The method can be used to manufacture brazing powders. The method is less hazardous and more cost effective than current methods, such as gas atomization, of preparing such braze materials.