Abstract: A high-remanence neodymium-iron-boron magnet, and a preparation method and the use thereof are provided. The neodymium-iron-boron magnet has crystal grains with an R-T-B type compound as a main structure, and a grain boundary phase. By means of adjusting the proportional relation of elements such as B, Cu, Ga, RE and Ti, the neodymium-iron-boron magnet can achieve a relatively high main phase grain volume ratio and effectively restrain the proportion of a B-rich phase in the grain boundary phase, such that the magnet has relatively high Br, and also has both good Hcj and squareness performance.

Abstract: A corrosion-resistant and high-performance sintered neodymium-iron-boron magnet, a preparation method therefor, and a use thereof are provided. The sintered neodymium-iron-boron magnet is prepared by pulverizing, forming, and sintering. The sintered neodymium-iron-boron magnet contains: 28.5 wt % to 32.5 wt % of R; 0.88 wt % to 0.94 wt % of B; 0.1 wt % to 0.3 wt % of Ga; 1.0 wt % to 3.0 wt % of Co; and 400 ppm to 1000 ppm of O. The sintered neodymium-iron-boron magnet capable of inhibiting reduction of coercive force and improving the coercive force can be obtained by means of an oxygen adding operation, and meanwhile, the corrosion resistance of the magnet can be improved.

Abstract: A permanent magnet material having the multilayer structure can obtain a high-performance permanent magnet material under the condition of a reduced content of Nd. By means of powder preparation, mixing, pressing, and sintering, the performance defect such as the reduction of the magnet property caused by CeY entering the main phase grains is effectively avoided, and the influence of the formation of a CeFe2 phase in the grain boundaries on the magnet property is also avoided. Moreover, by the introduction of M, the inhibition of CeY enrichment in the grain boundaries on the diffusion effect is avoided, a diffusion channel of heavy rare earth from the surface of the magnet to the interior is provided, and thus the diffusion effect is optimized, and the diffusion performance is significantly improved.

Abstract: An R-T-B based permanent magnet material, a preparation method therefor and use thereof are provided. The R-T-B permanent magnet material forms M oxides at the grain boundary triple point, such that oxygen is enriched at the grain boundary triple point, thereby accurately controlling the oxygen content in the magnet. The permanent magnet material and the preparation method of the present disclosure can prepare products with strong corrosion resistance under the condition of unchanged magnetic properties, and improve the formability in the pressing process, thereby improving the qualified rate of the products.

Abstract: An R-T-B based permanent magnet material, a preparation method therefor and use thereof are provided. The M compound is adhered to or coats the R-T-B based alloy powders to form a uniform coating layer on the surface of the neodymium-iron-boron powders, so that the rounding transformation of the R-T-B based alloy powders can be achieved, and further the wettability of the R-T-B based alloy powders is improved under the condition of significantly reducing the amount of heavy rare earth metals in the substrate. In addition, the grain boundary phases of M-R and/or M-T-R are present in the grain boundary of the R-T-B based permanent magnet material, the physicochemical properties of the grain boundary phases can be significantly improved, the distribution of the grain boundary phases is improved, and the grain boundary is strengthened.

Abstract: A sintered R—Fe—B permanent magnet has at least a grain boundary and composite main phase grains. The grain boundary has an RH-rich phase distributed in the form of an agglomerate within the grain boundary between the composite main phase grains, preferably at the intersection of any adjacent three or more composite main phase grains. The RH-rich phase is continuously distributed along the grain boundary in the form of a thin-layer stripe. The composite main phase grain has a core-shell structure, which includes a core structure having an R-T-B type phase structure and a shell structure on the outer layer of the core structure. The core structure contains Ce-rich main phase grains and Ce-poor main phase grains.