Stress sensitivity of inductance in NiCuZn ferrites

Iron rich, stoichiometric iron and iron deficient samples of NiCuZn ferrite were prepared by conventional ceramic double sintering process. The formation of single phase was confirmed by X-ray diffraction. Initial permeability measurements on these samples were carried out in the temperature range of 30-400 °C. The effect of external applied stress on the open magnetic circuit type coil with these ferrites was studied by applying uniaxial compressive stress parallel to the magnetising direction and the change in the inductance was measured. These studies show that stress sensitivity is more in the case of iron rich and stoichiometric iron samples while in the case of iron deficient samples the stress sensitivity was found to be less.