Effect of substitution with potassium and chromium oxides on the magnetic and electrical properties of Li-ferrite

Li-ferrite samples substituted with potassium and chromium oxides were prepared by using ceramic method. The chemical formula KyLi0.5-yCrxFe2.5-xO4 (x= 1.15, 1.2,... and 1.35; y = 0.0 and 0.05) was used. The Curie and compensation temperatures, T-c and T-o are decreased respectively with the increasing of the Cr content for all samples with potassium and without potassium. For Li-Cr ferrite, the values of T-o dose not change with potassium substitution ions relative to that sample without potassium at each Cr content. However, the Curie temperature, T-c and ac resistivity were increased (improved) with the potassium substitution relative to the samples without potassium at each Cr content. Furthermore, the magnetization was improved with the increasing of Cr content for, Li-ferrite at a temperature greater than the compensation temperature. (C) 2010 Elsevier B.V. All rights reserved.