锰锌铁氧体/锆钛酸铅复合陶瓷微结构及磁电性能研究

Microstructure and magnetoelectric properties of MZFO/PZT composite ceramics

采用共沉淀法和溶胶-凝胶法制备了Mn0.5 Zn0.5 Fe2O4/PbZr0.52 Ti0.48O3(MZFO/PZT)复合陶瓷,研究了MZFO/PZT质量比对复合陶瓷微结构及磁电性能的影响.通过XRD、SEM、EDS对复合陶瓷的相结构、表面微结构、成分进行表征,通过LCR数字电桥、铁电分析仪、振动样品磁强计对复合陶瓷的介电性、铁电性、磁性进行研究.结果表明:复合陶瓷中存在少量杂相(Fe2O3).不同质量比的复合陶瓷其居里温度(TC)略有不同,TC介于327℃和361℃之间.复合陶瓷的磁化强度与质量比呈非单调的变化关系.由于具有较强的界面效应,质量比为1:1.5的复合陶瓷具有最大的饱和磁化强度和剩余磁化强度,分别为2.2071 A·m^2/kg和0.0304 A·m^2/kg.施加磁场后复合陶瓷的极化强度明显减小,表现出负的磁电耦合系数.

Mn0.5 Zn0.5 Fe2 O4/PbZr0.52 Ti0.48 O3(MZFO/PZT)composite ceramics were prepared by combining chemical coprecipitation and sol-gel method.We studied how the MZFO/PZT mass ratio affect the microstructure and magnetoelectric properties.The phase,surface morphology and composition of the composite ceramics were characterized by XRD,SEM and EDS.The dielectric,ferroelectric and magnetic properties of the composite ceramics were investigated by LCR digital bridge,ferroelectric analyzer and vibrating sample magnetometer.The results show that a small amount of impurities(Fe2 O3)in the composites is observed.The Curie temperature(TC)varies with the mass ratio of MZFO/PZT from 327℃to 361℃.There is a non-monotonous relationship between the magnetization of the composites and the mass ratio of MZFO/PZT.And the best magnetic properties are obtained at the mass ratio of 1∶1.5 due to the strongest interface interaction,where the saturation and residual magnetization are 2.2071 A·m^2·kg^-1 and 0.0304 A·m^2·kg^-1 respectively.The polarization of the composite ceramics decreases obviously when applying magnetic field,which indicates negative magneto-electric coupling coefficient.