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Abstract: Effect of Pr–Ni substitution on structural and magnetic properties of Ca0.5Ba0.5−x Pr x Ni y Fe12−y O19 (x=0.00–0.10 and y=0.00–1.00) prepared by the sol–gel auto combustion method were investigated. The XRD analysis confirmed the single phase M-type hexa-ferrite structure. The lattice parameters were found to increase as Pr–Ni content increases, which is attributed to the ionic size of the implicated cations. The Pr–Ni seems to be completely soluble in the lattice. Transmission electron microscopy reveals that the grain size decreases with increase of Pr–Ni substitution. The coercivity and remanent magnetization ranges from 1511 to 1925 (Oe) and 21.4 to 26.5 (emu/g), respectively. The coercivity values of all the samples fall in the range of M-type hexa-ferrites. [Copyright &y& Elsevier]

Highlights: [•] Tb–Zn substituted Ca0.5Ba0.5Fe12O19 samples exhibit single magnetoplumbite phase. [•] Lattice parameters a and c have increasing values. [•] Coercivity can be tuned at lower substitution level [•] Crystallites size was found in the range 18–25nm by TEM and by Scherrer formula. [•] These hexa-ferrites are suitable for microwave devices and magnetic recording media. [Copyright &y& Elsevier]

Y-type hexa-ferrite Sr 1.8 Sm 0.2 Co 2 Ni 1.50 Fe 10.50 O 22 was synthesized via micro-emulsion route. Ferrite/PST composites were obtained by mixing the different ferrite ratio in the pure PST matrix. The microstructure was examined by scanning electron microscopy (SEM) and exhibited heterogonous distribution of grains. A keen observation of these SEM images revealed that the grain morphology changes noticeably with increasing ferrite filler contents. The electrical modulus, Cole–Cole plots and quality factor of ferrite polymer composites have been investigated in the frequency range (1 MHz to 3 GHz). The field dependent magnetic properties of the prepared samples were investigated at room temperature by using vibrating sample magnetometer (VSM). The shape of hysteresis loops and linearity of M s , M r , H c values vs. ferrite contents unfold that the ferrite nanoparticles are evenly dispersed within the composite. The occurrence of resonance at high frequency suggests that the present investigated composite samples are best candidate for multilayer chip inductors. [ABSTRACT FROM AUTHOR]

Highlights: [•] The decreasing trend of saturation magnetization is attributed to the weakening of exchange interactions. [•] The change in lattice constant at x >0.04 indicated the solubility limit of Gd in the spinel lattice. [•] The high coercive Li–Mg ferrites may be suitable for high frequency microwave absorption. [Copyright &y& Elsevier]