Structural and dielectric studies of magnesium substituted NiCuZn ferrites for microinductor applications

• The behaviour of NiMgCuZn ferrites synthesized for use as core materials for microinductor applications was investigated.
• A systematic study of the various properties such as electrical, mechanical and magnetic properties was carried out.
• An attempt was made to develop a soft ferrite which is used for microinductor applications.
• The high ɛ′ observed in present samples are suitable for fabrication of devices.

Ferrites have been the emerging focus of the recent scientific research. Based on the magnetic properties, ferrites are being used in many devices like permanent magnets, memory storage devices, etc., spinel ferrites using the electrical properties at high frequencies may result in the evolution of potential applications in new areas such as medicine, electronic, and electrical engineering. Therefore, Mg substituted NiCuZn ferrites compositions have been synthesized and characterized. Two series of samples with generic formulae viz. (1) Ni0.3MgxCu0.1Zn0.6−xFe2O4, where X = 0.1, 0.2 and 0.3 and (2) Ni0.35MgxCu0.05Zn0.6−xFe2O4, where X = 0.0, 0.1 and 0.2, were prepared by conventional double ceramic techniques. The structure and morphology were determined by X-ray powder diffractometry (XRD) and scanning electron microscope (SEM). The samples of the prepared compounds are in single phase cubic spinel structure. The lattice parameters, X-ray density and porosities of compounds were measured from XRD data. X-ray data reveal that the lattice parameters decreases with slight variations in NiCuZn ferrite compositions. A systematic study on the dielectric properties such as a dielectric constant (ɛ′), dielectric loss (ɛ″) and loss tangent (tan δ) have been investigated as a function of composition and frequency in the frequency range 100 Hz–1 MHz within the temperature variation of 30–360 °C. This attempt is made to understand the dielectric behaviour of present series of ferrites, which are developed for microinductor applications and the results are discussed in paper.