The invention provides a method for manufacturing a powder magnetic core through simple compression molding and capable of manufacturing a complicatedly shaped powder magnetic core with reliable high strength and insulating properties. The invention is directed to a method for manufacturing a powder magnetic core with a metallic soft magnetic material powder, the method including: a first step including mixing a soft magnetic material powder and a binder; a second step including compression molding the mixture obtained after the first step; a third step including performing at least one of grinding and cutting on the compact obtained after the second step; and a fourth step including heat-treating the compact after the third step, wherein in the fourth step, the compact is heat-treated so that an oxide layer containing an element constituting the soft magnetic material powder is formed on the surface of the soft magnetic material powder.

The invention provides a method for manufacturing a powder magnetic core through simple compression molding and capable of manufacturing a complicatedly shaped powder magnetic core with reliable high strength and insulating properties. The invention is directed to a method for manufacturing a powder magnetic core with a metallic soft magnetic material powder, the method including: a first step including mixing a soft magnetic material powder and a binder; a second step including compression molding the mixture obtained after the first step; a third step including performing at least one of grinding and cutting on the compact obtained after the second step; and a fourth step including heat-treating the compact after the third step, wherein in the fourth step, the compact is heat-treated so that an oxide layer containing an element constituting the soft magnetic material powder is formed on the surface of the soft magnetic material powder.

To obtain a magnetic core having an improved withstand voltage property while maintaining a high relative magnetic permeability, and the like. The magnetic core contains large particles observed as soft magnetic particles having a Heywood diameter of 5 μm or more and 25 μm or less and small particles observed as soft magnetic particles having a Heywood diameter of 0.5 μm or more and less than 5 μm in a cross section. C1<C2 is satisfied in which an average circularity of the small particles close to the large particles is C1 and an average circularity of all small particles observed in the cross section including small particles not close to the large particles is C2. The small particles close to the large particles are defined as small particles whose distance from centroids of the small particles to a surface of the large particles is 3 μm or less.

To obtain a magnetic core having an improved withstand voltage property while maintaining a high relative magnetic permeability, and the like. The magnetic core contains large particles observed as soft magnetic particles having a Heywood diameter of 5 μm or more and 25 μm or less and small particles observed as soft magnetic particles having a Heywood diameter of 0.5 μm or more and less than 5 μm in a cross section. C1<C2 is satisfied in which an average circularity of the small particles close to the large particles is C1 and an average circularity of all small particles observed in the cross section including small particles not close to the large particles is C2. The small particles close to the large particles are defined as small particles whose distance from centroids of the small particles to a surface of the large particles is 3 μm or less.

A coil component includes a body that is made of a composite material containing a resin material and metal powder, a coil conductor which is provided in the body and an end portion of which is exposed on an end face of the body, and a metal film that is provided on an outer surface of the body and that is electrically connected to the coil conductor on the end face in the outer surface. The outer surface of the body has a contact area that is in contact with the metal film. Multiple particles of the metal powder escape from the resin material and are in contact with each other in the contact area of the body.

A coil component includes a body that is made of a composite material containing a resin material and metal powder, a coil conductor which is provided in the body and an end portion of which is exposed on an end face of the body, and a metal film that is provided on an outer surface of the body and that is electrically connected to the coil conductor on the end face in the outer surface. The outer surface of the body has a contact area that is in contact with the metal film. Multiple particles of the metal powder escape from the resin material and are in contact with each other in the contact area of the body.

An electronic component includes an element body made of a composite material of a resin material and metal powder. A plurality of particles of the metal powder are exposed from the resin material and make contact with one another on the outer surface of the element.

An embodiment provides a magnetic core comprising a first powder and a second powder, wherein the hardness of the first powder is lower than that of the second powder, and the volume of the first powder is 40% to 60% with respect to the combined volume of the first powder and the second powder.

A dust core contains a powder of a crystalline magnetic material powder and a powder of an amorphous magnetic material. The sum of the content of the crystalline magnetic material powder and the content of the amorphous magnetic material powder is 83 mass percent or more. The mass ratio of the content of the crystalline magnetic material powder to the sum of the content of the crystalline magnetic material powder and the content of the amorphous magnetic material powder is 20 mass percent or less. The median diameter D50a of the amorphous magnetic material powder is greater than or equal to the median diameter D50c of the crystalline magnetic material powder. A 10% cumulative diameter D10a in a volume-based cumulative particle size distribution of the amorphous magnetic material powder is 9.5 μm or less.

A dust core contains a powder of a crystalline magnetic material powder and a powder of an amorphous magnetic material. The sum of the content of the crystalline magnetic material powder and the content of the amorphous magnetic material powder is 83 mass percent or more. The mass ratio of the content of the crystalline magnetic material powder to the sum of the content of the crystalline magnetic material powder and the content of the amorphous magnetic material powder is 20 mass percent or less. The median diameter D50a of the amorphous magnetic material powder is greater than or equal to the median diameter D50c of the crystalline magnetic material powder. A 10% cumulative diameter D10a in a volume-based cumulative particle size distribution of the amorphous magnetic material powder is 9.5 μm or less.