Mg–Cu–Zn Ferrites for Multilayer Inductors
Abstract:Mg–Cu–Zn ferrites can be sintered at T≤950°C to sufficient density and display adequate permeability profiles for application in multilayer ferrite inductors. The permeability and Curie temperature have to be optimized by proper selection of composition. Ferrites with <50 mol% Fe2O3 reveal enhanced densification behavior. Submicrometer powders prepared by fine milling show good sintering activity and density after firing at 900°C. Nano-size ferrite powders prepared by coprecipitation or flame synthesis lead to high density; maximum shrinkage already occurs at T<800°C. The use of Bi2O3 as a sintering additive further improves the densification, but also affects the microstructure and, hence, the permeability. A maximum permeability of i=450–500 is obtained.
Document Type: Research Article
Affiliations: Department of SciTec, University of Applied Sciences Jena, 07745 Jena, Germany
Publication date: October 1, 2007