Comparative Studies of NiMgCuZn composite ferrites with Equimolar (NiCuZn+MgCuZn) Nanocomposite ferrite useful for Microinductors Applications

In this paper, we report a comparative study on structural, magnetic, electric properties and stress sensitivity of the Ni0.175Mg0.125Cu0.15Zn0.55Fe2O4 with equimolar nano composite ferrite 0.5((Ni0.35Cu0.05Zn0.6Fe2O4)+ (Mg0.25Cu0.25Zn0.5 Fe2O4)) prepared by conventional double sintering technique, with a view to develop a ferrite composition for its use as core material for microinductor applications. The structural properties were estimated from X-ray diffraction patterns which confirms the formation of single phase cubic spinel structure and the grain size was estimated using SEM micrographs. Initial permeability measurements of samples were carried out in the temperature range of 30-400 0C at 100C temperature intervals, it was noticed that the initial permeability of Ni0.175Mg0.125Cu0.15Zn0.55Fe2O4 sample is drastically reducing when compared to equimolar composite ferrite. The effect of the external applied stress on the open magnetic circuit type coil with these ferrites was studied by applying uniaxial compressive stress parallel to magnetizing direction and the change in the inductance was measured. The variation of ratio of inductance (?L/L)% with external applied compressive stress was examined.