Preparation and investigation of dc conductivity and relative permeability of epoxy/Li–Ni–Zn ferrite composites

• Li–Ni–Zn ferrites have been prepared by the chemical co-precipitation method.
• Epoxy-ferrite composites have been prepared too.
• Structural and magnetic properties of all prepared samples were investigated.
• Results indicate that these composites may be promising for useful applications.

Ferrite nanoparticles – having the compositions Li(x/2)(Ni0.5Zn0.5)(1−x)Fe(2+x/2)O4 (x=0, 0.2, 0.3) – have been prepared by the co-precipitation method. The prepared powders have been divided into groups and sintered at different temperatures (373 K, 1074 K and 1473 K). X-Ray diffraction analysis (XRD) for all samples has confirmed the formation of the desired ferrites with crystallite sizes within the nanoscale (<100 nm). The dc conductivity, the relative permeability and the magnetization of the ferrite samples have been investigated and according to the results, the sample Li0.15(Ni0.5Zn0.5)0.7 Fe2.15O4 sintered at 1473 K has been chosen to prepare the composites. The particle size of this sample has been recalculated by using JEOL JEM-100SX transmission electron microscope and it has been found about 64.7 nm. Then, a pure epoxy sample and four pristine epoxy resin /Li0.15(Ni0.5Zn0.5)0.7 Fe2.15O4 composites have been prepared using different ferrite contents (20%, 30%, 40%, and 50%) wt.%. These samples have been characterized by Fourier transform infrared (FTIR) spectroscopy and their dc conductivity, relative permeability and magnetization have also been investigated. The obtained results indicate that the investigated composites may be promising candidates for practical applications such as EMI suppressor and high frequency applications.