Influence of Dy content on the microstructure and magnetic properties of Mg–Cu–Zn ferrites having the compositions Mg0.4Cu0.2Zn0.4DyxFe2-xO4 (where x = 0.0, 0.01, 0.02, 0.03, and 0.04) is reported in this study. An x-ray diffraction pattern has shown the single-phase cubic spinel structure for x \(\le\) 0.02, while a small peak of DyFeO3 coexists with the cubic spinel structure for x > 0.02. A microstructural study shows that the grain growth of Mg–Cu–Zn ferrites depends on the Dy content. It is seen that the average grain size is found to be larger at x = 0.02, which could be ascribed to the densification of the sample. The complex magnetic permeability measurement has shown that the enhancement of permeability is evidenced by the amount of Dy content. The saturation magnetization (Ms) and coercivity (Hc) have been observed for all the studied samples. It has been demonstrated that the magnetic softness property of the materials (for x = 0.02) has been improved due to the smaller value of Hc, which is also correlated to the grain size. Frequency-dependent dielectric constant and ac conductivity of the prepared samples have been investigated at 300 K. The dielectric property of the samples has shown dispersive behavior following the Maxwell–Wagner type of polarization. The Cole–Cole plots have exhibited a single semicircular arc for x ≤ 0.03, which indicates that the conduction mechanism occurred through the grain effect. An enhancement of the magnetic softness property has been improved due to the lower value of \({H}_{c}\) along with the larger value of the initial permeability at x = 0.02. It is inferred that the composition with Mg0.4Cu0.2Zn0.4Dy0.02Fe1.98O4 will be useful in an inductor material in high quality of coil.
