Higher d.c. resistivity of Li-Zn-Cd ferrites prepared by microwave sintering compared with conventional sintering

Abstract

Cd²⁺-substituted Li-Zn ferrites having the general formula Li_{0.4− x/2} ⁺Zn_0.2 ²⁺Cd _x ²⁺Fe_{2.4− x/2} ³⁺O₄ ²⁻ where x = 0.02, 0.03 and 0.04 have been prepared by both microwave sintering and conventional sintering. In the former case, sintering was done at 1050 °C for 25 min, whereas in the latter case sintering was done at 1050 °C for 6 h. The various structural properties, microstructures and d.c. resistivity of the samples prepared by the two techniques were compared. The study showed higher d.c. resistivity and higher activation energies in the samples prepared by microwave sintering. The mechanisms pertaining to the results are discussed.