An iron-based rare earth boron-based isotropic nanocomposite magnet alloy including: an alloy composition having a formula T.sub.100-x-y-z(B.sub.1-nC.sub.n).sub.xRE.sub.yZr.sub.zM.sub.m where T includes Fe, RE includes at least Nd, M is at least one of Al, Si, V, Cr, Ti, Mn, Cu, Zn, Ga, Nb, Mo, Ag, Hf, Ta, W, Pt, Au, and Pb, 4.2 atom %x5.0 atom %, 12.5 atom %y14.0 atom %, 0 atom %<z2.0 atom %, 0.0 atom %m5.0 atom %, and 0.0n0.5; and the magnet alloy includes a main phase having a RE.sub.2Fe.sub.14B tetragonal compound with a B content concentration lower than a stoichiometric composition of the RE.sub.2Fe.sub.14B tetragonal compound, and a grain boundary phase comprising a phase richer in Fe than the main phase surrounding the main phase, and the tetragonal compound is finer than a critical single-domain diameter of an average crystal grain size of 10 nm to less than 70 nm.

Disclosed are an anisotropic nanocrystalline rare earth permanent magnet and a preparation method thereof. The rare earth permanent magnet includes an RE-Fe-B matrix phase and a second phase, wherein the RE-Fe-B matrix phase includes main phase RE.sub.2Fe.sub.14B flaky nanocrystallines regularly arranged and an RE-rich phase around main phase grains, the main phase RE.sub.2Fe.sub.14B flaky nanocrystallines having an average grain size in a length direction of 70 nm to 800 nm and an average grain size in a thickness direction of 30 nm to 200 nm; and the second phase includes at least one selected from the group consisting of an M-Cu phase and an M-Cu-O phase, M being at least one selected from the group consisting of Ca and Mg.

A ribbon contains an alloy containing a rare earth element, iron, and boron. The ribbon has a surface R and a surface F located on a back side of the surface R. The surface R includes an amorphous region where only an amorphous phase of the alloy is exposed. The surface F includes a crystalline region where at least a crystalline phase of the alloy is exposed. The plurality of recesses are formed in the crystalline region. The surface R does not include the crystalline region where the plurality of recesses are formed.

Disclosed in the present invention is a preparation method for an anisotropic Nd.sub.2Fe.sub.14B/-Fe bulk nanocrystalline composite permanent magnet material. The preparation method comprises the following steps: preparing a master alloy; crushing the master alloy into bulks, and, by means of a melt rapid quenching method, preparing amorphous ribbons; grinding the amorphous ribbons to obtain amorphous powder; cold-pressing the powder into bulks; and placing the bulks into a stainless steel mold, and heating and then rolling same, the stainless steel mold being of a plate-shaped structure, and a chamber for accommodating the bulks being formed in the stainless steel mold along the thickness direction thereof. The present invention presses the NdFeB amorphous powder into bulks, embeds same in the stainless steel mold, and performs rolling at a temperature below a crystallization temperature, so as to achieve high-temperature amorphous material crystallization.

Disclosed in the present invention is a preparation method for an anisotropic Nd.sub.2Fe.sub.14B/-Fe bulk nanocrystalline composite permanent magnet material. The preparation method comprises the following steps: preparing a master alloy; crushing the master alloy into bulks, and, by means of a melt rapid quenching method, preparing amorphous ribbons; grinding the amorphous ribbons to obtain amorphous powder; cold-pressing the powder into bulks; and placing the bulks into a stainless steel mold, and heating and then rolling same, the stainless steel mold being of a plate-shaped structure, and a chamber for accommodating the bulks being formed in the stainless steel mold along the thickness direction thereof. The present invention presses the NdFeB amorphous powder into bulks, embeds same in the stainless steel mold, and performs rolling at a temperature below a crystallization temperature, so as to achieve high-temperature amorphous material crystallization.

The present disclosure relates to an anisotropic bulk magnet and a method for manufacturing the same. The anisotropic bulk magnet has a high fraction of a (Re,Ce).sub.2(Fe,Ti).sub.14B phase (magnetic phase), a low fraction of a (Re,Ce)Fe.sub.2 phase (non-magnetic phase), a fine crystal grain size, an excellent degree of crystal grain alignment, and a high rare earth element content at an interface of the crystal grain, and therefore, may have excellent magnetic properties such as coercivity and maximum magnetic energy product.

Disclosed are an anisotropic nanocrystalline rare earth permanent magnet and a preparation method thereof. The rare earth permanent magnet includes an RE-FeB matrix phase and a second phase, wherein the RE-FeB matrix phase includes main phase RE.sub.2Fe.sub.14B flaky nanocrystallines regularly arranged and an RE-rich phase around main phase grains, the main phase RE.sub.2Fe.sub.14B flaky nanocrystallines having an average grain size in a length direction of 70 nm to 800 nm and an average grain size in a thickness direction of 30 nm to 200 nm; and the second phase includes at least one selected from the group consisting of an M-Cu phase and an M-CuO phase, M being at least one selected from the group consisting of Ca and Mg.

A SmFeN-based magnetic material that includes: a main phase including a plurality of SmFeN-based crystal grains; and a grain boundary phase present between adjacent SmFeN-based crystal grains of the plurality of SmFeN-based crystal grains, and the grain boundary phase contains N, in which a ratio of a first content of N in the main phase to a second content of N in the grain boundary phase is 0.84 or more on an atomic basis.

Provided is a rare earth magnet capable of improving both residual magnetization and coercive force. The rare earth magnet of the present disclosure includes: a main phase; and a grain boundary phase present around the main phase. A total composition in atomic ratio is represented by the formula R.sup.1.sub.xT.sub.(100xyz)(B.sub.(1s)C.sub.s).sub.yM.sub.z, R.sup.1 is one or more elements selected from the group consisting of Nd, Ce, La, Pr, Gd, Tb, Dy, and Ho, T is one or more elements selected from the group consisting of Fe, Co, and Ni, M is one or more elements selected from the group consisting of Ga, Al, Cu, Au, Ag, Zn, In, and Mn and unavoidable impurity elements, and 12.0x20.0, 5.00y20.0, 0z2.0, and 0.07s0.17 are satisfied. The main phase has a crystal structure of R.sub.2Fe.sub.14B type, and R is a rare earth element.