Provided are Ce/Co/Cu permanent magnet alloys containing certain refractory metals, such as Ta and/or Hf, and optionally Fe which represent economically more favorable alternative to Sm-based magnets with respect to both material and processing costs and which retain and/or improve magnetic characteristics useful for GAP MAGNET applications.

Provided are Ce/Co/Cu permanent magnet alloys containing certain refractory metals, such as Ta and/or Hf, and optionally Fe which represent economically more favorable alternative to Sm-based magnets with respect to both material and processing costs and which retain and/or improve magnetic characteristics useful for GAP MAGNET applications.

The present invention discloses a method for preparing high-performance anisotropic rare-earth-free permanent magnets, comprising the steps of: forming alloy ingots by melting according to a nominal composition of Mn.sub.xBi.sub.100-x, (45≤×≤55); then coarsely crushing the alloy ingots and passing the crushed material through a 100-mesh sieve to obtain coarse powder; putting an appropriate amount of Mn.sub.xBi.sub.100-x alloy coarse powder obtained into a ball-milling tank together with non-magnetic steel balls, with a ratio of ball to powder of 10:1; adding an appropriate amount of ethanol as solvent, and then adding a non-ionic surfactant polyvinylpyrrolidone (PVP) accounting for 5-15% of the power mass to assist in low-energy ball milling; washing the slurry obtained in anhydrous ethyl alcohol, and orientating and curing the washed magnetic powder in a magnetic field after adding binder to obtain high-performance anisotropic Mn—Bi alloy magnets finally.

The present invention discloses a method for preparing high-performance anisotropic rare-earth-free permanent magnets, comprising the steps of: forming alloy ingots by melting according to a nominal composition of Mn.sub.xBi.sub.100-x, (45≤×≤55); then coarsely crushing the alloy ingots and passing the crushed material through a 100-mesh sieve to obtain coarse powder; putting an appropriate amount of Mn.sub.xBi.sub.100-x alloy coarse powder obtained into a ball-milling tank together with non-magnetic steel balls, with a ratio of ball to powder of 10:1; adding an appropriate amount of ethanol as solvent, and then adding a non-ionic surfactant polyvinylpyrrolidone (PVP) accounting for 5-15% of the power mass to assist in low-energy ball milling; washing the slurry obtained in anhydrous ethyl alcohol, and orientating and curing the washed magnetic powder in a magnetic field after adding binder to obtain high-performance anisotropic Mn—Bi alloy magnets finally.

Disclosed herein is a method comprising disposing a container containing a metal and/or ferromagnetic solid and abrasive particles in a static magnetic field; where the container is surrounded by an induction coil; activating the induction coil with an electrical current, to heat up the metallic or ferromagnetic solid to form a fluid; generating sonic energy to produce acoustic cavitation and abrasion between the abrasive particles and the container; and producing nanoparticles that comprise elements from the container, the metal and/or the ferromagnetic solid and the abrasive particles. Disclosed herein too is a composition comprising first metal or a first ceramic; and particles comprising carbides and/or nitrides dispersed therein. Disclosed herein too is a composition comprising nanoparticles comprising chromium carbide, iron carbide, nickel carbide, γ-Fe and magnesium nitride.

Disclosed herein is a method comprising disposing a container containing a metal and/or ferromagnetic solid and abrasive particles in a static magnetic field; where the container is surrounded by an induction coil; activating the induction coil with an electrical current, to heat up the metallic or ferromagnetic solid to form a fluid; generating sonic energy to produce acoustic cavitation and abrasion between the abrasive particles and the container; and producing nanoparticles that comprise elements from the container, the metal and/or the ferromagnetic solid and the abrasive particles. Disclosed herein too is a composition comprising first metal or a first ceramic; and particles comprising carbides and/or nitrides dispersed therein. Disclosed herein too is a composition comprising nanoparticles comprising chromium carbide, iron carbide, nickel carbide, γ-Fe and magnesium nitride.

Provided are Ce/Co/Cu permanent magnet alloys containing certain refractory metals, such as Ta and/or Hf, and optionally Fe which represent economically more favorable alternative to Sm-based magnets with respect to both material and processing costs and which retain and/or improve magnetic characteristics useful for GAP MAGNET applications.

Provided are Ce/Co/Cu permanent magnet alloys containing certain refractory metals, such as Ta and/or Hf, and optionally Fe which represent economically more favorable alternative to Sm-based magnets with respect to both material and processing costs and which retain and/or improve magnetic characteristics useful for GAP MAGNET applications.

A permanent magnet may include a Fe16N2 phase in a strained state. In some examples, strain may be preserved within the permanent magnet by a technique that includes etching an iron nitride-containing workpiece including Fe16N2 to introduce texture, straining the workpiece, and annealing the workpiece. In some examples, strain may be preserved within the permanent magnet by a technique that includes applying at a first temperature a layer of material to an iron nitride-containing workpiece including Fe16N2, and bringing the layer of material and the iron nitride-containing workpiece to a second temperature, where the material has a different coefficient of thermal expansion than the iron nitride-containing workpiece. A permanent magnet including an Fe16N2 phase with preserved strain also is disclosed.

A permanent magnet may include a Fe16N2 phase in a strained state. In some examples, strain may be preserved within the permanent magnet by a technique that includes etching an iron nitride-containing workpiece including Fe16N2 to introduce texture, straining the workpiece, and annealing the workpiece. In some examples, strain may be preserved within the permanent magnet by a technique that includes applying at a first temperature a layer of material to an iron nitride-containing workpiece including Fe16N2, and bringing the layer of material and the iron nitride-containing workpiece to a second temperature, where the material has a different coefficient of thermal expansion than the iron nitride-containing workpiece. A permanent magnet including an Fe16N2 phase with preserved strain also is disclosed.