CoFe 2 O 4 magnetic ceramic derived from gel and densified by spark plasma sintering

Cobalt ferrite (CoFe2O4) has been successfully synthesized by sol–gel technique. Pellets were prepared by spark plasma sintering technique (SPS) from CoFe2O4 sol–gel derived powder. The rapid sintering of CoFe2O4 pellet by SPS at 950 °C, leads to a dense ceramic (97%ρtheoretic) with average crystallite size of 71 nm. As revealed by X-ray diffraction and Mössbauer measurements, the obtained powder and SPS pellets are spinel ferrite with a cubic symmetry. Complex dielectric investigation performed on CoFe2O4 ceramic reveals multiple relaxation mechanisms while the magnetic measurements indicated a saturation magnetization value of ∼83 A m2/kg at room temperature, which make them useful for applications in microwave domain.