An anisotropic bonded magnet and a preparation method thereof are provided. By stacking magnets having different magnetic properties and/or densities, the magnets in the middle have high properties and the magnets at two ends and/or the periphery have low properties, thereby compensating for a property deviation caused by a difference in pressing densities during a pressing process, and improving the property uniformity of the magnets in an axial direction. The method solves the problem of “low in the middle and high at two ends” caused by the phenomenon of non-uniform magnetic field orientation and density along a height direction during orientation and densification.

An anisotropic rare earth sintered magnet represented by the formula (R.sub.1-aZr.sub.a).sub.x(Fe.sub.1-bCO.sub.b).sub.100-x-y(M.sup.1.sub.1-cM.sup.2.sub.c).sub.y. R is Sm and at least one element selected from rare earth elements, M.sup.1 is at least one element selected from the group consisting of V, Cr, Mn, Ni, Cu, Zn, Ga, Al, and Si, M.sup.2 is at least one element selected from the group consisting of Ti, Nb, Mo, Hf, Ta, and W, and x, y, a, b, and c each satisfy 7≤x≤15 at %, 4≤y≤20 at %, 0≤a≤0.2, 0≤b≤0.5, and 0≤c≤0.9. The magnet includes 80% by volume or more of a main phase composed of a compound of a ThMn.sub.12 type crystal, the main phase having an average crystal grain size of 1 μm or more, and an intergranular grain boundary phase being formed between adjacent main phase grains.

A rare earth sintered magnet includes a plurality of regions of a main phase each having an R.sub.2Fe.sub.14B crystal structure containing at least Nd as a rare earth element R and a grain boundary phase formed among the plurality of regions of the main phase. The grain boundary phase has Sm enriched portions in which Sm is enriched by Sm substitution in a crystalline NdO phase and heavy rare earth element RH enriched portions in which a heavy rare earth element RH is enriched at least on part of peripheries of the Sm enriched portions. This allows the heavy rare earth element RH to diffuse deeper into the rare earth sintered magnet while suppressing the deterioration of the magnetic properties.

An R-T-B based permanent magnet includes a rare earth element R, a transition metal element T, and B. The permanent magnet includes at least Nd as R. The permanent magnet includes at least Fe as T. The permanent magnet contains main phase grains and R-rich phases. The main phase grains include at least R, T, and B. The R-rich phases include at least R. The main phase grains observed in a cross section of the permanent magnet are flat. The cross section is parallel to an easy magnetization axis direction of the permanent magnet. Each of the R-rich phases is located between the main phase grains. An average value of intervals between the R-rich phases in the easy magnetization axis direction is from 5 μm to a width of the permanent magnet in the easy magnetization axis direction.

The present disclosure provides a rare earth magnet and manufacturing method thereof, which belongs to the field of rare earth magnet technology. The diffusion source is coated on the NdFeB base material, which is diffused and aged to obtain NdFeB magnet. The diffusion source alloy is R.sub.αM.sub.βB.sub.γFe.sub.100-α-β-γ, wherein R refers to at least one of Nd and Pr, and M Refers to at least one of Al, Cu, Ga. The Br reduction range is lower than 0.03 T, and Hcj growth is more than 318 kA/m.

A coated rare earth-iron-nitrogen-based magnetic powder including: a core region; a first coating portion provided outside the core region; and a second coating portion, the core region containing R, Fe, and N, where R represents at least one selected from the group consisting of Y, Ce, Pr, Nd, Gd, Tb, Dy, Ho, Er, Tm, Lu, and Sm, and if Sm is present, Sm constitutes less than 50 atm % of the total R content, the powder including, in an order from the core region, the first coating portion containing P and R, an average atomic concentration of R in the first coating portion being higher than and not higher than twice an average atomic concentration of R in the core region, and the second coating portion having average atomic concentrations of P and R lower than those in the first coating portion, respectively, and containing Fe.

Provided is an Sm—Fe—N rare earth magnet comprising Sm—Fe—N crystal grains. An oxygen content in the Sm—Fe—N rare earth magnet is 0.5% by mass or less on the basis of a total amount of the Sm—Fe—N rare earth magnet, and an average grain size of the Sm—Fe—N crystal grains is 1 μm or less.

The present invention involves a graphene-containing rare earth permanent magnet material and preparation method thereof. The graphene-containing rare earth permanent magnet material, comprising: 20.6 to 23.4 weight percent of neodymium, 6.6 to 7.5 weight percent of praseodymium, 0.95 to 1.20 weight percent of boron, 0.4 to 0.6 weight percent of cobalt, 0.11 to 0.15 weight percent of copper, 2.0 to 2.4 weight percent of lanthanum, 1.7 to 2.1 weight percent of cerium, 1 to 5 weight percent of graphene, a remainder being iron. The graphene-containing rare earth permanent magnet material exhibits excellent temperature resistance, good conductivity and magnet properties even without any heavy rare earth elements like terbium or dysprosium, which dramatically reduces the cost, promotes the efficient utilization of rare earth resources and improves product quality. The preparation method within this invention is simple to realize, easy to control, cost-effective and has high production efficiency and stable product performances.

Described herein are catalytic converter substrates or cores based on triply periodic minimal surfaces (TPMS) geometries, along with methods of making and using the same.

The disclosure refers to a NdFeB alloy powder for forming high-coercivity sintered NdFeB magnets. The NdFeB alloy powder includes NdFeB alloy core particles with a multi-layered coating, wherein the multi-layered coating comprises:

a first metal layer directly disposed on the NdFeB alloy core particles, wherein the first metal layer consists of at least one of Tb and Dy;

a second metal layer directly disposed on the first metal layer, wherein the second metal layer consists of at least one of W, Mo, Ti, Zr, and Nb; and

a third metal layer directly disposed on the second metal layer, wherein the third metal layer consists of (i) at least one of Pr, Nd, La, and Ce; or (ii) a combination of one of the group consisting of Cu, Al, and Ga and at least one of the group consisting of Pr, Nd, La, and Ce.