Abstract: A powder magnetic core capable of achieving a low loss in a high frequency range is provided. A powder magnetic core according to the present disclosure is a powder magnetic core in which a magnetic powder is bonded via a binder layer. A volume filling percentage of the magnetic powder included in the powder magnetic core is 85 volume % or higher, and a value obtained by dividing a BET specific surface area (m2/g) of the powder magnetic core by a specific surface area (m2/g) calculated using outer dimensions of the powder magnetic core is 5000 or less.

Abstract: A rare-earth cobalt permanent magnet having excellent magnetic characteristics, a method for manufacturing such a rare-earth cobalt permanent magnet, and a device including such a rare-earth cobalt permanent magnet are provided. A rare-earth cobalt permanent magnet consisting of 23 to 27 mass % of a rare-earth element R including Sm, 4.0 to 5.0 mass % of Cu, 22 to 27 mass % of Fe, 1.7 to 2.5 mass % of Zr, and a remainder consisting of Co and unavoidable impurities, in which the rare-earth cobalt permanent magnet includes a plurality of crystal grains and grain boundary parts, and a size of a cell structure constituting the crystal grain is 100 to 600 nm.

Abstract: A rare-earth cobalt permanent magnet having excellent magnetic characteristics, a method for manufacturing such a rare-earth cobalt permanent magnet, and a device are provided. A rare-earth cobalt permanent magnet consists of, when a rear-earth element including at least Sm is represented by R, 23 to 27 mass % of R, 1.0 to 5.0 mass % of Cu, 18 to 25 mass % of Fe, 1.5 to 3.0 mass % of Zr, and a remainder consisting of Co and unavoidable impurities, in which the rare-earth cobalt permanent magnet includes a plurality of crystal grains and grain boundary parts, and a concentration of Cu is at least two times a concentration of Zr in the grain boundary parts.

Abstract: Provided is a method of manufacturing a soft magnetic dust core. The method includes: preparing coated powder including amorphous powder made of an Fe-B-Si-P-C-Cu-based alloy, an Fe-B-P-C-Cu-based alloy, an Fe-B-Si-P-Cu-based alloy, or an Fe-B-P-Cu-based alloy, with a first initial crystallization temperature Tx1 and a second initial crystallization temperature Tx2; and a coating formed on a surface of particles of the amorphous powder; applying a compacting pressure to the coated powder or a mixture of the coated powder and the amorphous powder at a temperature equal to or lower than Tx1?100 K; and heating to a maximum end-point temperature equal to or higher than Tx1?50 K and lower than Tx2 with the compacting pressure being applied.

Abstract: A rare-earth cobalt permanent magnet according to the present disclosure comprises: 24 to 26 mass % of a rare-earth element R including Sm; 25 to 27 mass % of Fe; 4.0 to 7.0 mass % of Cu; 2.0 to 3.5 mass % of Zr; and Co and an unavoidable impurity as a remainder. The rare-earth element R is any one of a combination of Sm and Nd, a combination of Sm and Pr, or a combination of Sm, Nd, and Pr. The rare-earth cobalt permanent magnet includes a cell phase that includes a crystalline phase of a Th2Zn17 structure and a cell wall that includes a crystalline phase of an RCo5 structure enclosing the cell phase, and the concentration of the rare-earth element R in the cell wall is higher than the concentration of the rare-earth element R in the cell phase by no less than 25 atomic %.

Abstract: Provided is a soft magnetic dust core having high density and favorable properties. A method of manufacturing a soft magnetic dust core includes: preparing coated powder including amorphous powder made of an Fe—B—Si—P—C—Cu-based alloy, an Fe—B—P—C—Cu-based alloy, an Fe—B—Si—P—Cu-based alloy, or an Fe—B—P—Cu-based alloy, with a first initial crystallization temperature Tx1 and a second initial crystallization temperature Tx2; and a coating formed on a surface of particles of the amorphous powder; applying a compacting pressure to the coated powder or a mixture of the coated powder and the amorphous powder at a temperature equal to or lower than Tx1?100 K; and heating to a maximum end-point temperature equal to or higher than Tx1?50 K and lower than Tx2 with the compacting pressure being applied.

Abstract: Provided is a soft magnetic dust core having high density and favorable properties. A method of manufacturing a soft magnetic dust core includes: preparing coated powder including amorphous powder made of an Fe—B—Si—P—C—Cu-based alloy, an Fe—B—P—C—Cu-based alloy, an Fe—B—Si—P—Cu-based alloy, or an Fe—B—P—Cu-based alloy, with a first initial crystallization temperature Tx1 and a second initial crystallization temperature Tx2; and a coating formed on a surface of particles of the amorphous powder; applying a compacting pressure to the coated powder or a mixture of the coated powder and the amorphous powder at a temperature equal to or lower than Tx1?100 K; and heating to a maximum end-point temperature equal to or higher than Tx1?50 K and lower than Tx2 with the compacting pressure being applied.