Abstract：The CoFe2O4/BaTiO3 composite powder material was prepared by the combination of ferromagnetic cobalt ferrite and ferroelectric barium titanate by sol-gel method. The phase composition, molecular structure, micro- morphology, magnetic properties of the composite powder and ferroelectric properties of the sintered body were analyzed and characterized by XRD, infrared spectrometer(IR), SEM, TEM, vibrating sample magnetometer(VSM) and ferroelectric analyzer. The results show that the CoFe2O4/BaTiO3 composite powder prepared by sol-gel method is composed of cobalt ferrite and barium titanate phases. The morphology of the powder is spherical, and the particle size is uniform. The grain size increases with the increase of synthetic temperature. The magnetic properties of the material increase with increasing the ratio of cobalt ferrite. When the molar ratio of cobalt ferrite and barium titanate is n(CoFe2O4):n(BaTiO3)=2:1, the saturation magnetization intensity of the composite is 40.01 (A∙m2)/kg, and the residual magnetization intensity is 20.59 (A∙m2)/kg. Meanwhile, a ceramic was prepared using this powder. The electric field is 4.12×106 V/m, and the remanent polarization is 0.30 C/m2. It has good ferromagnetic and ferroelectric properties at the same time.
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2018, Vol. 23 
