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arXiv · 1103.5021

Temperature dependence of core loss in cobalt substituted Ni-Zn-Cu ferrites

Frederic Mazaleyrat·Richard Lebourgeois·Eric Labouré·Antony Lucas
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Abstract

The temperature dependence of core loss in cobalt substituted Ni-Zn-Cu ferrites was investigated. Co2+ ions are known to lead to a compensation of the magneto-crystalline anisotropy in Ni-Zn ferrites, at a temperature depending on the cobalt content and the Ni/Zn ratio. We observed similar behaviour in Ni-Zn-Cu and it was found that the core loss goes through a minimum around this magneto-crystalline anisotropy compensation. Moreover, the anisotropy induced by the cobalt allowed a strong decrease of core loss, a ferrite having a core loss of 350 mW/cm3 at 80 ^\circ C was then developed (measured at 1.5 MHz and 25 mT). This result represents an improvement of a factor 4 compared to the state of art Ni-Zn ferrites.

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Frederic Mazaleyrat, Richard Lebourgeois, Eric Labouré, Antony Lucas. 2011-03-25. Temperature dependence of core loss in cobalt substituted Ni-Zn-Cu ferrites. https://doi.org/10.1016/j.jmmm.2010.10.037

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