Effect of cobalt addition on the magneto-crystalline anisotropy parameter of sintered NiZn ferrites evaluated from magnetization curves
Abstract
This paper investigates the effect of the cobalt addition on the magneto-crystalline anisotropy parameter of some polycrystalline ferrites. Magnetization curves have been experimentally determined at different temperatures on Ni1-xZnxFe2O4 sintered samples with or without cobalt addition. In each case, a law of approach to saturation has been fitted to the measured data in order to extract the anisotropy parameter K1 representative for the polycrystalline material.
Besides, measurement of the complex susceptibility and power core-loss up to 5 MHz has been performed. This approach allows a discussion on the role of cobalt addition on the power core-loss mitigation. It has been found that the substitution with 0.02 mol. of Co leads to a small decrease in the K1 values. This evolution is consistent with the rise in the rotational permeability. However, the change in K1 cannot account for the core-loss reduction with Co. Rather, it is confirmed that Co hinders the domain wall displacement and subsequent dissipation up to an induction level that depends on the grain size.- Publication:
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Journal of Magnetism and Magnetic Materials
- Pub Date:
- March 2019
- DOI:
- 10.1016/j.jmmm.2018.10.030
- Bibcode:
- 2019JMMM..473...92F
- Keywords:
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- Spinel ferrite;
- NiZnCu;
- Co addition;
- Core-loss;
- High frequency