Influence of SiO₂ Additive on the High-Frequency Magnetic Properties of Sr-Doped Co₂Z Hexaferrite

Abstract:

In this work, SiO₂ has been selected to be introduced into the system to improve the high-frequency magnetic properties of Ba_1.5Sr_1.5Co₂Fe₂₄O₄₁ hexaferrites. The influence of SiO₂ additive on the phase composition, microstructures and high-frequency magnetic properties of the samples prepared by solid-state reaction were investigated. The results indicate that the major phase of doped samples is Z-type ferrite. The addition of SiO₂ causes a decrease of the average grain size. Permeability measurements indicate that SiO₂ doping significantly improves the magnetic characteristics of those samples. With the doping content of SiO₂ increasing from 0 to 8wt%, the initial permeability decreases from 5.8 to 2.6, and the cut-off frequency rises up from 1.5GHz to over 1.8GHz. Meanwhile, the quality factor of the samples sintered at 1200°C varies with the SiO₂ content, and a maximum quality factor at 1GHz of Q=14 was found for x=4wt%. The improvements of magnetic properties and the high quality factors are crucial for applications of Z-type hexaferrites in high-frequency communication systems.

• Periodical: Materials Science Forum (Volume 787)
• Pages: 332-337
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.787.332
• Online since: April 2014
• Authors: Li Yun Gan, Ying Li Liu, Yu Wang, Kai Yang, Dainan Zhang
• Keywords: Magnetic Property, Quality Factor, SiO₂, Sr-Doped Co₂Z

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