Fabrication and performance optimization of Mn—Zn ferrite/EP composites as microwave absorbing materials

Abstract

Magnesium-substituted Mn0.8Zn0.2Fe2O4 ferrite is synthesized by the sol—gel combustion method using citrate acid as the complex agent. The electromagnetic absorbing behaviors of ferrite/polymer coatings fabricated by dispersing Mn—Zn ferrite into epoxy resin (EP) are studied. The microstructure and morphology are characterized by X-ray diffraction and scanning electron microscope. Complex permittivity, complex permeability, and reflection loss of ferrite/EP composite coating are investigated in a low frequency range. It is found that the prepared ferrite particles are traditional cubic spinel ferrite particles with an average size of 200 nm. The results reveal that the electromagnetic microwave absorbing properties are significantly influenced by the weight ratio of ferrite to polymer. The composites with a weight ratio of ferrite/polymer being 3:20 have a maximum reflection loss of −16 dB and wide absorbing band. Thus, the Mn—Zn ferrite is the potential candidate in electromagnetic absorbing application in the low frequency range (10 MHz—1 GHz).

Cation distributions estimated using the magnetic moments of the spinel ferrites Co1−xCrxFe2O4at 10 K

“…Co ferrites with striking magnetic, electrical, and optical properties have potential applications in various fields, such as recording tapes, permanent magnets, hard disc recording media, read-write heads, magnetic drug delivery, catalysis, color imaging, magnetic refrigeration, magnetic resonance imaging (MRI) contrast enhancement, magnetic cell separation, etc. [1][2][3][4][5] CoFe 2 O 4 is a typical spinel ferrite with an (A)[B] 2 O 4 structure. Each spinel unit cell contains eight formula units.…”

Enhanced soft magnetic properties of iron powders through coating MnZn ferrite by one-step sol–gel synthesis*

“…MnZn ferrite can be employed as an promising candidate because of its high resistivity and excellent magnetic properties. [16,17] Li et al [18] obtained MnZn/FeSiAl SMCs by using the solvothermal method, which has better magnetic properties compared with mica coating. Nonetheless, the interface state between the coating and magnetic powder remains unclear and the coating layer was incomplete because the powders were mechanically mixed with as-synthesized MnZn ferrites.…”

Layer‐by‐Layer Self‐Assembled Ferrite Multilayer Nanofilms for Microwave Absorption

“…Microwave absorbing materials, commonly known as radar absorbing materials, are in high demand for microwave absorption coatings on the surface of military stealth aircraft to avoid detection by enemy radar. A number of microwave absorbing materials have been explored for this application: conducting fibers [1,2], ferromagnetic composites [3], carbon nanotubes [4], and ferrites [5][6][7][8] are frequently used. In particular, the unique microwave absorbing properties of ferrite nanoparticles, resulting from both magnetic and dielectric losses, have been explored by many groups [9][10][11][12][13][14][15].…”