Abstract: A method includes mixing first and second alloys to form a mixture, pressing the mixture within a first magnetic field to form a magnet having anisotropic particles of the first alloy aligned with a magnetic moment of the magnet, and heat treating the magnet within a second magnetic field to form elongated grains from the second alloy and align the elongated grains with the moment.

Abstract: An inductor that is configured to store energy in a magnetic field includes a wire and a core. The wire is configured to deliver electrical current to the inductor to generate the magnetic field. The core is disposed radially about the wire. The core comprises magnetic particles that are suspended in a non-magnetic matrix. The magnetic particles are arranged such that a magnetic permeability of the core increases in a direction that extends radially outward from the wire along a cross-sectional area of the magnetic core from a first region that is adjacent to the wire to a second region that is adjacent to an outer periphery of the magnetic core.

Abstract: A rotor for an electric machine includes a core comprised of stacked laminations that define pockets between a hub portion and a pole portion. Each of the pockets are configured to receive magnetic material and define center cavities between regions of magnetic material to eliminate a flux leakage path between the magnetic materials. A cured mixture including an epoxy and a magnetic powder is disposed within the center cavities. The magnetic material may include sintered magnets and a cured mixture.

Abstract: A power inductor includes a housing and a magnetic core disposed in the housing. The core includes a first segment and a second segment spaced apart from each other to define a gap. The first and second segments are supported in the housing such that the they are movable relative to each other to increase and decrease the size of the gap. A fluid having a positive thermal expansion coefficient is disposed in the housing such that expansion and contraction of the fluid due to change in temperature increases and decreases the gap, respectively.

Abstract: A method of forming an annealed magnet includes positioning a magnetizing array ring concentrically with a ring of bulk magnetic material to form an assembly, the magnetizing array ring having a magnetic field defining directions for orienting grains of the ring of bulk magnetic material, placing the assembly in a furnace, and operating the furnace to anneal the ring of bulk magnetic material and grow the grains in the directions. A magnetic array assembly includes a furnace; and an assembly including (i) a ring of bulk magnetic material having grains and (ii) a magnetizing array ring concentric with the ring of bulk magnetic material, and having a magnetic field defining directions for orienting the grains during growth thereof in a presence of heat from the furnace.

Abstract: A method of increasing volume ratio of magnetic particles in a MnBi alloy includes operating a jet miller fed with a MnBi alloy powder containing magnetic particles and non-magnetic particles with gas flow parameters selected such that, only for the magnetic particles, a gas drag force is greater than a centrifugal force within the jet miller to separate the magnetic particles from the non-magnetic particles.

Abstract: A method comprising sintering a Mn and Bi powder compact at a first temperature for a first predetermined duration, based on the first temperature, and sintering the compact at a second temperature, less than the first temperature, for a second predetermined duration, greater than the first duration, is disclosed. The sintering at a first temperature for a first predetermined duration generates a predetermined MnBi LTP transition driving force to decrease a formation energy barrier for transition to MnBi LTP. Sintering the compact at the second temperature for the second predetermined duration forms a magnet containing the MnBi LTP.

Abstract: A method of forming a permanent magnet includes processing a mixture of mischmetal-Fe—B particles having an average MM2Fe14B grain size below 500 nm and low melting point (LMP) alloy particles into a compact defining grain boundaries between MM2Fe14B grains; hot-pressing the compact; and hot-deforming the compact to diffuse the LMP alloy particles into the grain boundaries, thickening the grain boundaries and modifying a surface region composition of the MM2Fe14B grains.

Abstract: A method includes depositing a layer of alloy particles including rare earth permanent magnet phase above a substrate, laser scanning the layer while cooling the substrate to melt the particles, selectively initiate crystal nucleation, and promote columnar grain growth in a same direction as an easy axis of the rare earth permanent magnet phase. The method also includes repeating the depositing and scanning to form bulk anisotropic rare earth alloy magnet with aligned columnar grains.

Abstract: A method of increasing volume ratio of magnetic particles in a MnBi alloy includes depositing a MnBi alloy powder containing magnetic particles and non-magnetic particles on a sloped surface having a magnetic field acted thereupon. The method further includes collecting falling non-magnetic particles while separated magnetic particles are magnetically retained on the sloped surface.

Abstract: A method includes mixing first and second alloys to form a mixture, pressing the mixture within a first magnetic field to form a magnet having anisotropic particles of the first alloy aligned with a magnetic moment of the magnet, and heat treating the magnet within a second magnetic field to form elongated grains from the second alloy and align the elongated grains with the moment.

Abstract: An internally segmented magnet is disclosed. The magnet may include a first layer of a permanent magnetic material, a second layer of a permanent magnetic material, and an insulating layer separating the first and second layers. The insulating layer may include a ceramic mixture of at least a first ceramic material and a second ceramic material. The mixture having a melting point of up to 1,100° C. and may be a eutectic, or near eutectic, composition. The magnet may be formed by forming a first layer of powdered permanent magnetic material, depositing an insulating layer over the first layer, depositing a second layer of powdered permanent magnetic material over the insulating layer to form an internally segmented magnet stack, and sintering the magnet stack. The ceramic materials may include a halogen and an alkaline earth metal, alkali metal, or a metal having a +3 or +4 oxidation state.

Abstract: A grain boundary diffusion method for a rare-earth (RE) magnet is provided. The method includes coating particles of the RE magnet with a coating material. Each RE magnet particle includes a plurality of grains. The coated particles are then simultaneously heat treated and compacted. The heat treated, compacted, and coated particles are then formed into a rare earth magnet. In a form of the method, the heat treated, compacted, and coated particles are hot deformed prior to being formed into a rare earth magnet. Another form of the method achieves the grain boundary diffusion without first sintering the rare earth magnet.

Abstract: A method comprising sintering a Mn and Bi powder compact at a first temperature for a first predetermined duration, based on the first temperature, and sintering the compact at a second temperature, less than the first temperature, for a second predetermined duration, greater than the first duration, is disclosed. The sintering at a first temperature for a first predetermined duration generates a predetermined MnBi LTP transition driving force to decrease a formation energy barrier for transition to MnBi LTP. Sintering the compact at the second temperature for the second predetermined duration forms a magnet containing the MnBi LTP.

Abstract: Magnets and methods of making the magnets are disclosed. The magnets may have high coercivity and may be suitable for high temperature applications. The magnet may include a plurality of grains of a Nd—Fe—B alloy having a mean grain size of 100 to 500 nm. The magnet may also comprise a non-magnetic low melting point (LMP) alloy, which may include a rare earth element and one or more of Cu, Ga, and Al. The magnets may be formed from a Nd—Fe—B alloy powder produced using HDDR and jet milling, or other pulverization process. The powder may have a refined grain size and a small particle size and particle size distribution. The LMP alloy may be mixed with a powder of the Nd—Fe—B alloy or it may be diffused into a consolidated Nd—Fe—B bulk magnet. The LMP alloy may be concentrated at the grain boundaries of the bulk magnet.

Abstract: Magnets and methods of making the magnets are disclosed. The magnets may have high coercivity and may be suitable for high temperature applications. The magnet may include a plurality of grains of a Nd—Fe—B alloy having a mean grain size of 100 to 500 nm. The magnet may also comprise a non-magnetic low melting point (LMP) alloy, which may include a rare earth element and one or more of Cu, Ga, and Al. The magnets may be formed from a Nd—Fe—B alloy powder produced using HDDR and jet milling, or other pulverization process. The powder may have a refined grain size and a small particle size and particle size distribution. The LMP alloy may be mixed with a powder of the Nd—Fe—B alloy or it may be diffused into a consolidated Nd—Fe—B bulk magnet. The LMP alloy may be concentrated at the grain boundaries of the bulk magnet.

Abstract: Magnets and methods of making the magnets are disclosed. The magnets may have high coercivity and may be suitable for high temperature applications. The magnet may include a plurality of grains of a Nd—Fe—B alloy having a mean grain size of 100 to 500 nm. The magnet may also comprise a non-magnetic low melting point (LMP) alloy, which may include a rare earth element and one or more of Cu, Ga, and Al. The magnets may be formed from a Nd—Fe—B alloy powder produced using HDDR and jet milling, or other pulverization process. The powder may have a refined grain size and a small particle size and particle size distribution. The LMP alloy may be mixed with a powder of the Nd—Fe—B alloy or it may be diffused into a consolidated Nd—Fe—B bulk magnet. The LMP alloy may be concentrated at the grain boundaries of the bulk magnet.

Abstract: A method of increasing volume ratio of magnetic particles in a MnBi alloy includes operating a jet miller fed with a MnBi alloy powder containing magnetic particles and non-magnetic particles with gas flow parameters selected such that, only for the magnetic particles, a gas drag force is greater than a centrifugal force within the jet miller to separate the magnetic particles from the non-magnetic particles.

Abstract: In at least one embodiment, a hybrid permanent magnet is disclosed. The magnet may include a plurality of anisotropic regions of a Nd—Fe—B alloy and a plurality of anisotropic regions of a MnBi alloy. The regions of Nd—Fe—B alloy and MnBi alloy may be substantially homogeneously mixed within the hybrid magnet. The regions of Nd—Fe—B and MnBi may have the same or a similar size. The magnet may be formed by homogeneously mixing anisotropic powders of MnBi and Nd—Fe—B, aligning the powder mixture in a magnetic field, and consolidating the powder mixture to form an anisotropic hybrid magnet. The hybrid magnet may have improved coercivity at elevated temperatures, while still maintaining high magnetization.

Abstract: A segmented magnet is disclosed comprising first and second layers of permanent magnetic material and an insulating layer therebetween. The insulating layer may include a rare earth element and a ceramic mixture including at least first and second ceramic materials. The ceramic materials may include a halogen and an alkaline earth metal, alkali metal, or a metal having a +3 or +4 oxidation state. The rare earth element may comprise up to 30 wt. % of the insulating layer. The segmented magnet may be formed by applying the insulating layer to a first sintered permanent magnet layer, stacking a second sintered permanent magnet layer in contact with the insulating layer and spaced from the first sintered permanent magnet layer, and heating the formed magnet stack. The heating step may include annealing the magnet stack at an annealing temperature within 100° C. of the melting point of the ceramic mixture.