A method for producing a phosphate-coated SmFeN-based anisotropic magnetic powder, the method includes a phosphate treatment of adding an inorganic acid to a slurry containing an SmFeN-based anisotropic magnetic powder, water, and a phosphate compound to adjust a pH of the slurry to a range of 1 to 4.5 to form a phosphate-coated SmFeN-based anisotropic magnetic powder having a surface coated with a phosphate.

A responsive material having an elastomeric matrix in which ferromagnetic particles are dispersed so as to have a predetermined magnetization pattern which, when exposed to an external magnetic field, changes the shape of the responsive material from an initial shape to a predetermined transformed shape dictated by the magnetization pattern. An initial shape of the responsive material is formed by direct ink printing while applying magnetic fields to a dispensing nozzle to align the particles and gives rise to the desired magnetization pattern.

Provided are a SmFeN magnetic powder which is superior not only in water resistance and corrosion resistance but also in hot water resistance, and a method of preparing the powder. The present invention relates to a method of preparing a magnetic powder, comprising: plasma-treating a gas; surface-treating a SmFeN magnetic powder with the plasma-treated gas; and forming a coat layer on the surface of the surface-treated SmFeN magnetic powder.

Example nanoparticles may include an iron-based core, and a shell. The shell may include a non-magnetic, anti-ferromagnetic, or ferrimagnetic material. Example alloy compositions may include an iron-based grain, and a grain boundary. The grain boundary may include a non-magnetic, anti-ferromagnetic, or ferrimagnetic material. Example techniques for forming iron-based core-shell nanoparticles may include depositing a shell on an iron-based core. The depositing may include immersing the iron-based core in a salt composition for a predetermined period of time. The depositing may include milling the iron-based core with a salt composition for a predetermined period of time. Example techniques for treating a composition comprising core-shell nanoparticles may include nitriding the composition.

A method of stabilizing soft particles to create dried nanocomposite magnets includes coating a plurality of soft particles with a layer of SiO.sub.2, the soft particles being nanoparticles, creating a composite by mixing the soft particles with hard phase via a solution phase based assembly, annealing the composite, washing the composite with an alkaline solution to remove SiO.sub.2, and compacting the composite to create dried nanocomposite magnets.

A method of producing a rare earth magnetic powder, the method including: heat-treating a mixture containing a SmFeN-based magnetic powder containing Sm, Fe, and N and a modifier powder containing Zn; and dispersing the heat-treated SmFeN-based magnetic powder using a resin-coated metal media or a resin-coated ceramic media.

Example nanoparticles may include an iron-based core, and a shell. The shell may include a non-magnetic, anti-ferromagnetic, or ferrimagnetic material. Example alloy compositions may include an iron-based grain, and a grain boundary. The grain boundary may include a non-magnetic, anti-ferromagnetic, or ferrimagnetic material. Example techniques for forming iron-based core-shell nanoparticles may include depositing a shell on an iron-based core. The depositing may include immersing the iron-based core in a salt composition for a predetermined period of time. The depositing may include milling the iron-based core with a salt composition for a predetermined period of time. Example techniques for treating a composition comprising core-shell nanoparticles may include nitriding the composition.

A method for producing a permanent magnet, comprising the step: (a) providing a powder of a magnetic material, (b) coating the powder particles with a coating of a diamagnetic or paramagnetic coating material, (c) compressing the coated particles to form a pressed part, (d) heat treatment to sinter the coating material at a temperature less than a temperature suitable for sintering the magnetic material, while the coating material transfers to a matrix of a diamagnetic or paramagnetic material, which embeds the particles of the magnetic material, and (e) magnetizing the magnetizable material in an external magnetic field, wherein the steps (c), (d) and (e) are carried out in any order successively or at the same time in any desired combination. The nanostructured permanent magnet that can be produced by mean of said method comprises cores of a permanently magnetic material having a mean particle diameter of no more than 1 m and a matrix of a diamagnetic or paramagnetic material in which the cores are embedded.

To provide a rare earth magnet having excellent coercive force and a production method thereof. A rare earth magnet, wherein the rare earth magnet comprises a magnetic phase containing Sm, Fe, and N, a Zn phase present around the magnetic phase, and an intermediate phase present between the magnetic phase and the Zn phase, wherein the intermediate phase contains Zn and the oxygen content of the intermediate phase is higher than the oxygen content of the Zn phase; and a method for producing a rare earth magnet, including mixing a magnetic raw material powder having an oxygen content of 1.0 mass % or less and an improving agent powder containing metallic Zn and/or a Zn alloy, and heat-treating the mixed powder.

A method of producing a magnetic powder includes performing a phosphorus treatment to obtain a phosphorus compound and a rare earth-iron-nitrogen-based magnetic powder, the phosphorus treatment including adding an inorganic acid to a slurry containing: a rare earth-iron-nitrogen-based magnetic powder containing R, Fe, and N, where R represents at least one of rare earth elements selected from the group consisting of Y, Ce, Pr, Nd, Gd, Tb, Dy, Ho, Er, Tm, Lu, and Sm, and if R contains Sm, Sm constitutes less than 50 atm % of a total R atomic content; water; and a phosphorus-containing substance.