Magnetic Losses in Composite Materials
2008 (English)In: Journal of Physics D: Applied Physics, ISSN 0022-3727, E-ISSN 1361-6463, Vol. 41, no 13, 135005- p.Article in journal (Refereed) Published
We discuss some of the problems involved in homogenization of a composite material built from ferromagnetic inclusions in a nonmagnetic background material. The small signal permeability for a ferromagnetic spherical particle is combined with a homogenization formula to give an effective permeability for the composite material. The composite material inherits the gyrotropic structure and resonant behaviour of the single particle. The resonance frequency of the composite material is found to be independent of the volume fraction, unlike dielectric composite materials. The magnetic losses are described by a magnetic conductivity which can be made independent of frequency and proportional to the volume fraction by choosing a certain bias. Finally, some concerns regarding particles of small size, i.e. nanoparticles, are treated and the possibility of exciting exchange modes are discussed. These exchange modes may be an interesting way to increase losses in composite materials.
Place, publisher, year, edition, pages
2008. Vol. 41, no 13, 135005- p.
Capillarity, Composite materials, Composite micromechanics, Dielectric materials, Ferromagnetic materials, Ferromagnetism, Liquids, Magnetic domains, Magnetic materials, Resonance, Titration, Effective permeability, Gyrotropic structure, Magnetic (CE), Magnetic conductivities, Non magnetic, Resonance frequencies, Single particles, Small signals, Small size, Spherical particles
Other Electrical Engineering, Electronic Engineering, Information Engineering
IdentifiersURN: urn:nbn:se:kth:diva-8540DOI: 10.1088/0022-3727/41/13/135005ISI: 000256928100037ScopusID: 2-s2.0-48249129687OAI: oai:DiVA.org:kth-8540DiVA: diva2:13891
QC 20100906. Uppdaterad från accepted till published (20100906).2008-05-282008-05-282010-09-06Bibliographically approved