Study on the structural and electromagnetic properties of Tm-substituted Mg–Mn ferrites by a solution combustion method

The effect of thulium ion substitution for iron on the structural and electromagnetic properties of Mg–Mn ferrites is reported. The Mg0.9Mn0.1TmxFe1.8−xO4 ferrite compositions with x=0.0, 0.025, 0.05, and 0.075 were synthesized by a nitrate–citrate solution combustion method. Tm substitution had taken place and this was found to produce a secondary phase TmFeO3. The crystallite size of the powder calcined at 500°C was in the range of 9–13nm. Subsequently, the calcined ferrite powders were compacted and sintered at 1250°C. It was found that the physical and magnetic properties had changed with Tm contents. Bulk density was found to decrease from 4.26 to 3.82g/cm3 with increasing Tm contents. It was also found that the saturation magnetization (Ms=38.41–23.62emu/g) had decreased with an increase of Tm. In this study, the highest resistivity (39.84×106Ωcm) was observed for Mg0.9Mn0.1Fe1.725Tm0.075O4. The correlation between structural and electromagnetic properties of the Tm-substituted samples is interpreted based on phase composition as well as microstructure. •Nano-Tm substituted Mg–Mn ferrites were prepared by a solution combustion method.•The saturation magnetization (Ms=38.41–23.62emu/g) had decreased with increase of Tm.•The highest resistivity (39.84×106Ωcm) was observed for Mg0.9Mn0.1Fe1.725Tm0.075O4.•Co-relation between structural and electromagnetic properties of the Tm substituted samples is interpreted on the basis of phase composition and microstructure.