| CPC H01F 1/20 (2013.01) [B22F 1/05 (2022.01); B22F 1/102 (2022.01); B22F 2302/45 (2013.01); H01F 27/255 (2013.01)] | 13 Claims |
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1. A magnetic material comprising:
an aggregate of a plurality of magnetic particles, wherein
in a first planar region observed by a scanning electron microscope or an optical microscope such that from 50 to 200 of the magnetic particles are included in one visual field,
when a first magnetic particle of the magnetic particles is rotated by 360/n degrees (n is any integer equal to or greater than 2) around a first gravity center position which is a gravity center position of the first magnetic particle in the first planar region, an area of the first magnetic particle after rotation overlaps with an area of the first magnetic particle before rotation by 90% or more,
for a first direction and a second direction orthogonal to each other in the first planar region, when maximum lengths of the first magnetic particle passing through the first gravity center position are defined as a first particle diameter and a second particle diameter, respectively, gravity center positions of from nine to eleven magnetic particles are present, on a first band portion in a rectangular shape having, with the first gravity center position as a center, a length four or five times the first particle diameter on each of both sides in the first direction and a width equal to the second particle diameter in the second direction, and
for magnetic particles present in the first planar region, when α is a number-based 50% cumulative frequency distribution D50 of maximum lengths in the first direction passing through respective gravity center positions, a 10% cumulative frequency distribution D10 is equal to or greater than 0.9% and a 90% cumulative frequency distribution D90 is equal to or less than 1.1α,
surfaces of the magnetic particles are covered with insulating film containing at least two elements selected from the group consisting of C, N, O, P, and Si,
in the first planar region, for a third direction intersecting the first direction, and a fourth direction orthogonal to the third direction, when maximum lengths of the first magnetic particle passing through the first gravity center position are defined as a third particle diameter and a fourth particle diameter, respectively, gravity center positions of from nine to eleven magnetic particles are present, on a second band portion in a rectangular shape having, with the first gravity center position as a center, a length four or five times the third particle diameter on each of both sides in the third direction and a width equal to the fourth particle diameter in the fourth direction, and
the first direction and the third direction are not orthogonal to each other.
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