Dielectric behaviour of Cu1−xTixFe2O4 ferrites

Abstract

The ac conductivity, dielectric constant, dielectric loss, and dielectric loss tangent of mixed ferrites Cu1−xTixFe2O4 (where x = 0 to 0.7) are measured at various frequencies and different temperatures. At different temperatures, it was observed that the ac conductivity for f 0.4 increases slowly with f, and for f > 104 Hz increases strongly with f. The dielectric loss (e″) decreases with increasing frequency much more rapid than the dielectric constant (e′). The general trend for all compositions is that e′ and e″ decrease with increasing frequency, and the average decrease rates are 77.5 and 98.9%, respectively. For x ≦ 0.4, the activation energy is nearly constant (about 0.30 eV), but for x > 0.4, increases rapidly with increasing composition x. For x ≦ 0.4, not noticeable change in dielectric values (e′ and e″) was observed at room temperature and constant frequency 105 Hz, but tan δ decreases rapidly with increase of Ti4+ content.