Thermal conductivity of the ferrites Ni0.65Zn0.35CuxFe2−xO4

Abstract

A series of samples of the type 0.1, 0.2, 0.3, 0.4 and 0.5) were prepared by a ceramic technique. The existence of a single phase was confirmed by Xray studies. The thermal conductivity and specific heat were measured at 53~ The thermal conductivity had a minimum value at x = 0.3, due to the maximum porosity at this composition. The phonon frequency was estimated to have an optimum value at x = 0.3, due to the increase in phonon scattering.

Phase Transition (Spinel-Ortho) Ferrite Doped with Holmium

“…This can be illustrated to increase g the A.C. conductivity with rising temperature because the hopping rate of electrons between Fe 3+ ions and Fe 2+ are thermally activated. The behavior of our results is similar to that in previous work [22].…”

“…The formation of orthorhombic phase as a result of Ho addition decreases the conduction process between Fe 2+ and Fe 3+ leading to the decrease of electric polarization and hence the dielectric constant. The behavior of our results is similar to that in previous work [22]. Figure 14 shows the variation of tanδ (dielectric loss) as a function of temperature at different Ho content at 1 KHz.…”