Controllable morphology, dielectric, magnetic and reflection loss characteristics of ferrite/wax composites for low-loss applications

Highlights: • The microwave characteristics of Ba_(1x)Sr_xFe₁₂O₁₉ ferrite/paraffin wax composites have been evaluated from 0.13 GHz to 3 GHz. • The dielectric and magnetic loss tangent were reduced with the increase in frequency and content of Sr²⁺ ions. • The AC conductivity occupies range of 4.64x10⁴ to 2.92x10⁴ (ohm. cm)¹ and decreases with doping of Sr²⁺ ions. • All compositions pass through 99.77% of microwave signal without attenuation. • The prepared compositions can be used for designing microwave passive components in wireless communication. -- Abstract: In this work, composites of M-type Ba_(1−x)Sr_xFe₁₂O₁₉ hexagonal ferrite (x=0.0, 0.2, 0.4, 0.6, 0.8 and 1.0) and paraffin wax have been prepared. Microwave characterization of the prepared composites was performed with a vector network analyzer from 0.13 GHz to 3 GHz. The dependence of Sr²⁺ ion content on different compositions was determined in terms of grain morphology, dielectric, magnetic, conductivity, and reflection loss (RL) properties. The grain size varied with dopants and rendered a significant effect on material parameters. The dielectric and magnetic loss tangent were reduced with the increase in frequency and content of Sr²⁺ ions. The AC conductivity followed the trend of gradual increase with frequency and x=1.0 composition attained the lowest value encompassing the frequency spectrum mostly. The observed RL peaks have been narrow in Ba_0.8Sr_0.2Fe₁₂O₁₉/wax composite and broad in SrFe₁₂O₁₉/wax composite along with the low frequency spectrum. x=0.6 composition has-0.35×10⁻³ dB reflection loss at 0.15 GHz. All compositions revealed more than 99.77% unattenuated (low-loss) microwave signal, with −0.01 dB bandwidth ≥1.50 GHz, and owe good scope for their application in low-loss microwave devices.