Search

Highlights: [•] Sr-substituted Y-type hexaferrites synthesized by sol–gel method have been investigated. [•] Platelet grains with well defined hexagonal shape are suitable for microwave absorbers. [•] Saturation magnetization values were calculated by the law of approach to saturation. [•] Coercivity of a few hundred oersteds found for all samples is suitable for EM materials. [ABSTRACT FROM AUTHOR]

Highlights: [•] W-type hexagonal ferrites substituted with different divalent ions have been investigated. [•] Platelets like grains with hexagonal shape are suitable for microwave absorbers. [•] Saturation magnetization was calculated by the law of approach to saturation. [•] The low value of coercivity for the investigated sample is favorable for EM materials. [•] The materials are good for suppression of EMI and as radar absorbing materials (RAMs). [ABSTRACT FROM AUTHOR]

Highlights: [•] Al-substituted W-type hexaferrites with formula BaCo2Al x Fe16−xO27 were investigated. [•] DC resistivity increased with increasing Al contents due to unavailability of Fe3+ ions. [•] The increased value of resistivity is favorable for microwave absorption. [•] The coercivity (Hc ) values for all the samples lie in the range of a few hundred oersteds. [•] The low value of Hc is suitable for EM materials, switching and sensing applications. [ABSTRACT FROM AUTHOR]

Highlights: [•] A series of X-type hexagonal ferrites were prepared by sol–gel method. [•] The XRD analysis showed that the X-type hexagonal structure. [•] The c/a ratio of these samples falls in the range of X-type hexagonal ferrites. [•] The magnetic properties enhances with the increase of Nd–Co contents. [•] The samples show the reflection loss at smaller frequencies. [Copyright &y& Elsevier]

Abstract: We have prepared BaCd2−x Sr x Fe16O27 (x =0, 0.5, 1, 1.5 and 2.0) W-type hexagonal ferrites by standard ceramic method. In this work, the structural, dielectric and magnetic properties have been studied of the prepared samples. The XRD analysis of the samples reveals single phase behavior sintered at 1400°C for 6h. The saturation magnetization (M s ) shows increasing behavior with the increasing concentration of Sr2+. While the coercivity (H c ) decreases rapidly up to 409G for x =1.5 and then increases for (x >1.5) due to the preference of Cd2+ for tetrahedral sites and the number of spin-down magnetic ions. The real and imaginary parts of the dielectric constant (ɛ′,ɛ″) and dielectric loss tangent (tan δ) are determined in the frequency range 0.1–107 Hz. It is observed that both the real and imaginary parts of the dielectric constant and tan δ decrease with the increasing concentration of Sr2+, which is due to the contribution of Cd2+ ions in addition to Fe3+ and Fe2+ ions to interfacial polarization. [Copyright &y& Elsevier]