Sintering temperature optimization for terbium doped strontium hexaferrite with improved microwave properties

Abstract

Optimizing reaction parameters while undergoing synthesis process can help in customization of materials to be used in high frequency devices. However, optimization in terms of reaction parameters remains a challenge and not much success has been achieved so far even after years of sustained research efforts in this direction. We in this paper report our results on synthesization of M−type hexaferrite nanoparticles with composition Sr1-xTbx Fe12O19 (where × varies from 0 to 0.10 in steps of 0.02) using chemical co-precipitation method. Thorough investigations have been carried out to find out the variation in crystallite size of nanoparticles with change in terbium ion concentration from 2 % −10 %, using XRD results and TEM micrographs. Detailed analysis has also been carried out to study the impact of increase in sintering temperature on the dielectric properties for a frequency range of 1–6 GHz using Vector network Analyzer. While dielectric constant values were found to be in the range of 4–21, absorbance showed a variation of 5 % with change in sintering temperature. The average value of dielectric loss for pure strontium hexaferrite sample has been found to be 6.0 × 10−2 and vary between 5.1 × 10−2 and 1.38 × 10−1 for other compositions. According to the results, the sintering temperature of 1200 °C has been established as optimum for the sintering of the material. The material thus synthesized is suitable for millimeter wave antenna applications.