Mg–Mn–Al FERRITES FOR HIGH FREQUENCY APPLICATIONS

Abstract

The effect of substitution of nonmagnetic Al 3+ ions on the electrical and magnetic properties of Mg–Mn ferrites was studied in the ferrite series Mg 0.9 Mn 0.1 Al x Fe 2-x O 4 where x varied from 0–0.5 in steps of 0.1. The incorporation of Al 3+ ions in place of Fe 3+ ions results in a decrease of the lattice parameter owing to the smaller size of the substituted ions. The increase in dc resistivity has been observed at the expense of the deterioration of magnetic properties. A significant reduction in the values of the initial permeability, saturation magnetization and Curie temperature has been observed with successive increase of Al 3+ ions. These changes in properties have been explained on the basis of various models and other relevant factors, like modified cation distribution and magnetic interactions. The high dc resistivity, thereby lowering the dielectric losses, and the low value of the saturation magnetization are the desired characteristics of aluminium-substituted Mg–Mn ferrites used to prepare microwave devices operating in L, S and C bands.

Investigations on structural, electrical and dielectric properties of yttrium substituted Mg-ferrites

“…Further Mg-Mn ferrites have also been reported to be highly suitable for memory and switching circuits in digital computers and phase shifters [5]. These ferrites have been synthesized for their utilization in several microwave devices operating at L, S and C bands [6].…”

COMPARATIVE STUDY OF DIELECTRIC BEHAVIOR OF Mn0.4Zn0.6Fe2O4 NANOFERRITE BY CITRATE PRECURSOR METHOD

“…[1][2][3][4][5] The quality of ferrite powder has strong influence on the performance of the final device. Soft ferrites are among the most widely used magnetic materials having low cost, high performance in high frequency applications.…”

Influence of Cd2+ and Cr3+ substitutions on the magnetization and permeability of magnesium ferrites

“…Trivalent substitution of Nd 3+ ions causes a decrease in the magnetic moment of Mg-Zn ferrites [8]. Al 3+ -substituted Mg-Mn ferrite has been studied by Singh et al [11] for high-frequency applications.…”