Electric, magnetic and high frequency properties of screen printed ferrite-ferroelectric composite thick films on alumina substrate

Abstract

Purpose – The purpose of this article is to study the effect of ferrite content on electric, magnetic and microwave properties of screen-printed y(Ni0.4Co0.2Cd0.4Fe2O4) + (1 − y)Pb(Zr0.52Ti0.48)O3 (y = 0.0, 0.15, 0.30, 0.45, 1.0) thick films on alumina. Design/methodology/approach – Thick films of ferrite–ferroelectric composite on alumina substrate have been delineated using screen printing technique. The structural analysis was carried out using X-ray diffraction method and scanning electron microscopy. The DC electrical resistivity was measured using the two-probe method. The magnetic measurement was carried out using a vibrating sample magnetometer. Microwave absorption was studied in the 8-18 GHz frequency range by using the vector network analyzer (N5230A). The permittivity in the 8-18 GHz frequency range was measured by using voltage standing wave ratio slotted section method. Findings – The formation of two individual ferrite–ferroelectric phases in composite thick films was confirmed by the X-ray diffraction patterns. The scanning electron microscope morphologies show the growth of cobalt-substituted nickel cadmium ferrite grains which are well dispersed in lead zirconium titanate matrix. The DC electrical resistivity increases with increase in ferrite content and decreases with increase in temperature. The present ferrite shows ferromagnetic nature and it increases saturation magnetization and coercivity of the composite thick films. Tuning properties are observed in the Ku-band and broadband X-band microwave absorption is observed in the composite thick films. The imaginary part of permittivity increases with an increase in ferrite content, which increases microwave absorption. The real part of microwave permittivity varied from 17 to around 22 with an increase in ferrite content and it decreases with frequency. The microwave conductivity, which increases with an increase in ferrite content, reveals the loss of polaron conduction, which supports the dielectric loss in the microwave region. Originality/value – Electric, magnetic and microwave properties of screen-printed y(Ni0.4Co0.2Cd0.4Fe2O4) + (1 − y)Pb(Zr0.52Ti0.48)O3 (y = 0.0, 0.15, 0.30, 0.45, 1.0) composite thick films on alumina substrate is reported for the first time.

Design of liquid composite materials for shielding electromagnetic fields

“…For the convenience of applying a protective material on the surface, ready-made paints of two types were chosen as a matrix. The first is the acrylic water-dispersion paint VD˗AK˗22W (Belarus) (ρ=1.03 g/cm 3 ), the second is the geopolymer paint MK 3/18˗9.20 (Ukraine) (ρ=1.15 g/cm 3 ).…”

“…This is due to an increase in the number and density of the location of electrical and electronic equipment in production facilities, an increase in the load on power structures. Study [3] identified the protective properties of a material made of polymer matrix and a metal filler made of ferrite of micro size. Recently, a significant part of studies addresses the development of compositions based on metal and metal-containing nanostructures.…”

Studying the shielding of an electromagnetic field by a textile material containing ferromagnetic nanostructures

“…It also refers to materials with microwires [3]. These shortcomings are not inherent in the materials with a uniform distribution of the shielding substance in the body of a material (matrix) [4]. However, ferrite particles in the matrix are of large size, which makes the material thickness (1 mm or larger) unacceptable for the manufacture of protective clothing.…”

“…The use of the ethyl alcohol-based fluid, with the subsequent neutralization of oleic acid by an alkaline solution, turned out to be impractical because of the washout or chemical destruction of the nano-particles by alkali, which was confirmed experimentally. 4. In order to determine the possibility of manufacturing special clothing from the designed material aimed to protect against electrical and magnetic fields, we simulated the magnetic field distribution in the human body using a finite element method and the Comsol software.…”

Research into protective properties of electromagnetic screens based on the metal-containing nanostructures

“…That is why at low (13-15 % by weight) content of metal, reflection coefficients amount to 0.3-0.6, which is unacceptable under production conditions with a large density of arrangement of technological equipment. These deficiencies are partially eliminated in the elastic electromagnetic screen based on ferrite-aluminum [8]. An analysis revealed that it is very difficult to manufacture and is very expensive.…”