### Abstract

We investigate if the demagnetization factor for a randomly packed powder of magnetic spheroidal particles depend on the shape of the spheroidal particles and what the internal variation in magnetization is within such a powder. A spheroid is an ellipsoid of revolution, i.e. an ellipsoid with two semi-major axis being equal. The demagnetization factor is calculated as function of particle aspect ratio using two independent numerical models for several different packings, and assuming a relative permeability of 2. The calculated demagnetization factor is shown to depend on particle aspect ratio, not because of direct magnetic interaction but because the particle packing depend on the aspect ratio of the particles. The relative standard deviation of the magnetization across the powder was 3–8%, increasing as the particle shape deviates from spherical, while the relative standard deviation within each particle was relatively constant around 5%.

Original language | English |
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Pages (from-to) | 417-422 |

Number of pages | 6 |

Journal | Journal of Magnetism and Magnetic Materials |

Volume | 476 |

DOIs | |

Publication status | Published - 15 Apr 2019 |

### Cite this

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*Journal of Magnetism and Magnetic Materials*, vol. 476, pp. 417-422. https://doi.org/10.1016/j.jmmm.2019.01.005

**The demagnetization factor for randomly packed spheroidal particles.** / Bjørk, R.; Zhou, Z.

Research output: Contribution to journal › Article › Research › peer-review

TY - JOUR

T1 - The demagnetization factor for randomly packed spheroidal particles

AU - Bjørk, R.

AU - Zhou, Z.

PY - 2019/4/15

Y1 - 2019/4/15

N2 - We investigate if the demagnetization factor for a randomly packed powder of magnetic spheroidal particles depend on the shape of the spheroidal particles and what the internal variation in magnetization is within such a powder. A spheroid is an ellipsoid of revolution, i.e. an ellipsoid with two semi-major axis being equal. The demagnetization factor is calculated as function of particle aspect ratio using two independent numerical models for several different packings, and assuming a relative permeability of 2. The calculated demagnetization factor is shown to depend on particle aspect ratio, not because of direct magnetic interaction but because the particle packing depend on the aspect ratio of the particles. The relative standard deviation of the magnetization across the powder was 3–8%, increasing as the particle shape deviates from spherical, while the relative standard deviation within each particle was relatively constant around 5%.

AB - We investigate if the demagnetization factor for a randomly packed powder of magnetic spheroidal particles depend on the shape of the spheroidal particles and what the internal variation in magnetization is within such a powder. A spheroid is an ellipsoid of revolution, i.e. an ellipsoid with two semi-major axis being equal. The demagnetization factor is calculated as function of particle aspect ratio using two independent numerical models for several different packings, and assuming a relative permeability of 2. The calculated demagnetization factor is shown to depend on particle aspect ratio, not because of direct magnetic interaction but because the particle packing depend on the aspect ratio of the particles. The relative standard deviation of the magnetization across the powder was 3–8%, increasing as the particle shape deviates from spherical, while the relative standard deviation within each particle was relatively constant around 5%.

UR - http://www.scopus.com/inward/record.url?scp=85059556993&partnerID=8YFLogxK

U2 - 10.1016/j.jmmm.2019.01.005

DO - 10.1016/j.jmmm.2019.01.005

M3 - Article

VL - 476

SP - 417

EP - 422

JO - Journal of Magnetism and Magnetic Materials

JF - Journal of Magnetism and Magnetic Materials

SN - 0304-8853

ER -