Microwave studies of ferrite-ferroelectric composites prepared through self propagating auto combustion route

Abstract

The structural and microwave properties of (y) Ni1-xCdx Fe2O4 and (1 - y) Ba0.8Sr0.2TiO3 (x = 0.2, 0.4, 0.6 and y = 0.15, 0.30 and 0.45) composites synthesized by self propagating auto combustion route was studied. X-ray diffraction patterns reveal this method can produce two phases simultaneously. The porosity increases with increase in ferrite content in the composite. The SEM morphologies show the growth of cadmium substituted nickel ferrite grains which are well dispersed in barium strontium titanate (BST) matrix. The composite material shows microwave absorption of about 0.575 in a broad band from 8-12 GHz. The permittivity varied from 7 to around 43 with increase in ferrite content. The microwave conductivity measurements reveal the loss of polaron conduction which supports the dielectric loss in the microwave region.