The dust core comprises a plurality of soft magnetic iron-based particles, a coating layer disposed on each of the surfaces of the soft magnetic iron-based particles, an interstitial layer disposed between the coating layers, and a nanopowder disposed between the soft magnetic iron-based particles. The coating layer is a layer of a compound comprising Fe, Si, O, B and N; and the nanopowder is a powder of a compound comprising O, N and at least one element selected from the group consisting of Fe, Si, Zr, Co, Al, Mg, Mn and Ni.

The dust core comprises a plurality of soft magnetic iron-based particles, a coating layer disposed on each of the surfaces of the soft magnetic iron-based particles, an interstitial layer disposed between the coating layers, and a nanopowder disposed between the soft magnetic iron-based particles. The coating layer is a layer of a compound comprising Fe, Si, O, B and N; and the nanopowder is a powder of a compound comprising O, N and at least one element selected from the group consisting of Fe, Si, Zr, Co, Al, Mg, Mn and Ni.

Provided is an Fe-based nanocrystalline alloy powder. The Fe-based nanocrystalline alloy powder has a chemical composition, excluding inevitable impurities, represented by a composition formula of Fe.sub.aSi.sub.bB.sub.cP.sub.dCu.sub.eM.sub.f, where the M in the composition formula is at least one element selected from the group consisting of Nb, Mo, Zr, Ta, W, Hf, Ti, V, Cr, Mn, C, Al, S, O, and N, 79 at %≤a≤84.5 at %, 0 at %≤b<6 at %, 0 at %<c≤10 at %, 4 at %<d≤11 at %, 0.2 at %≤e≤0.53 at %, 0 at %≤f≤4 at %, a+b+c+d+e+f=100 at %, a degree of crystallinity is more than 10% by volume, and an Fe crystallite diameter of the Fe-based nanocrystalline alloy powder is 50 nm or less.

Provided is an Fe-based nanocrystalline alloy powder. The Fe-based nanocrystalline alloy powder has a chemical composition, excluding inevitable impurities, represented by a composition formula of Fe.sub.aSi.sub.bB.sub.cP.sub.dCu.sub.eM.sub.f, where the M in the composition formula is at least one element selected from the group consisting of Nb, Mo, Zr, Ta, W, Hf, Ti, V, Cr, Mn, C, Al, S, O, and N, 79 at %≤a≤84.5 at %, 0 at %≤b<6 at %, 0 at %<c≤10 at %, 4 at %<d≤11 at %, 0.2 at %≤e≤0.53 at %, 0 at %≤f≤4 at %, a+b+c+d+e+f=100 at %, a degree of crystallinity is more than 10% by volume, and an Fe crystallite diameter of the Fe-based nanocrystalline alloy powder is 50 nm or less.

A drum-type magnetic body includes: a pair of flange parts that are facing each other; and a shaft part connecting the pair of flange parts, wherein an outer periphery of a cross section of the shaft part in a direction orthogonal to an axis of the shaft part has an oval shape constituted by a pair of parallel straight parts and a pair of arc parts connecting end parts of the pair of parallel straight parts, and the flange parts each have an outer principal face running orthogonal to the axis of the shaft part, and the pair of parallel straight parts are running in parallel with a longitudinal direction of the principal face of the flange part.

A drum-type magnetic body includes: a pair of flange parts that are facing each other; and a shaft part connecting the pair of flange parts, wherein an outer periphery of a cross section of the shaft part in a direction orthogonal to an axis of the shaft part has an oval shape constituted by a pair of parallel straight parts and a pair of arc parts connecting end parts of the pair of parallel straight parts, and the flange parts each have an outer principal face running orthogonal to the axis of the shaft part, and the pair of parallel straight parts are running in parallel with a longitudinal direction of the principal face of the flange part.

A coil component may include a body having a support member including a through hole, a coil disposed on at least one of an upper surface and a lower surface of the support member, and a magnetic material encapsulating the coil and the support member, and filling the through hole. The coil includes a coil pattern. The coil component further includes an external electrode connected to the coil. At least one of the upper surface and the lower surface of the support member includes a groove, having a shape corresponding to a shape of the coil pattern, and at least a portion of the coil pattern is embedded in the groove.

A coil component may include a body having a support member including a through hole, a coil disposed on at least one of an upper surface and a lower surface of the support member, and a magnetic material encapsulating the coil and the support member, and filling the through hole. The coil includes a coil pattern. The coil component further includes an external electrode connected to the coil. At least one of the upper surface and the lower surface of the support member includes a groove, having a shape corresponding to a shape of the coil pattern, and at least a portion of the coil pattern is embedded in the groove.

A sintered material contains Fe in an amount of from 8 mol % to 37 mol % in terms of Fe.sub.2O.sub.3, Zn in an amount of from 30 mol % to 60 mol % in terms of ZnO, Cu in an amount of from 1 mol % to 7 mol % in terms of CuO, Ni in an amount of from 3 mol % to 17 mol % in terms of NiO, and Si in an amount of from 7 mol % to 28 mol % in terms of SiO.sub.2. A mole ratio (SiO.sub.2/Fe.sub.2O.sub.3) of the SiO.sub.2 to the Fe.sub.2O.sub.3 is from 0.2 to 3.5. The sintered material contains B in an amount of from 0.05 mol parts to 0.5 mol parts.

A sintered material contains Fe in an amount of from 8 mol % to 37 mol % in terms of Fe.sub.2O.sub.3, Zn in an amount of from 30 mol % to 60 mol % in terms of ZnO, Cu in an amount of from 1 mol % to 7 mol % in terms of CuO, Ni in an amount of from 3 mol % to 17 mol % in terms of NiO, and Si in an amount of from 7 mol % to 28 mol % in terms of SiO.sub.2. A mole ratio (SiO.sub.2/Fe.sub.2O.sub.3) of the SiO.sub.2 to the Fe.sub.2O.sub.3 is from 0.2 to 3.5. The sintered material contains B in an amount of from 0.05 mol parts to 0.5 mol parts.