Dielectric and Electromechanical Coupling Factor in Co0.4Zn0.6NixFe2-xO4 Ferrite

The electromechanical coupling factor K-p of systems Co0.4Zn0.6NixFe2-xO4 (x=0.0, 0.2, 0.4, 0.6, 0.8 and 1.0) is larger than 1 and reaches a maximum value at Ni content x=0.8. The ultrasonic velocity is determined and decreases with increasing Ni contents to minimum value at x = 0.8. This composition is very important to the used in medical ultrasonic and under water sound transducers and condensers. The dielectric constant is measured and increases to optimum value at x = 0.8. The dielectric constant increases also with rising temperature to maximum value near the transition temperature. The dielectric anisotropy was also estimated.