低温烧结CoFe2O4-(PZN-PZT)多铁复合材料磁电性能研究

采用传统陶瓷工艺和低温烧结制备了CoFe₂O₄-(PZN-PZT)多铁复合陶瓷, 研究了混合方式、PZT包覆和成分变化对其结构、磁性能、磁电耦合性能的影响。XRD图谱和TEM照片显示, 采用溶胶-凝胶和包覆搅拌混合的方法获得了CoFe₂O₄/PZT核壳结构粉末, 在CoFe₂O₄表面形成了10~20 nm的钙钛矿PZT壳层。EDS结果显示, 低温烧结和阻挡层可以有效抑制两相间的元素扩散。SEM照片和磁电性能结果显示, 相对未包覆研磨混合工艺, 包覆搅拌混合可以提高磁性颗粒复合含量, 获得较好烧结匹配性, 有效提高材料的磁电耦合性能。研究结果表明, 包覆搅拌混合制备体积比为4:6的CoFe₂O₄-(PZN-PZT)样品, 经1000℃烧结, 在10 kHz下获得最大磁电耦合系数(18.3 mV/(cm·Oe))。

Magnetoelectric Properties of Low Temperature Sintered CoFe2O4-(PZN-PZT) Multiferroic Composite Materials

CoFe₂O₄-(PZN-PZT) multiferroic composite ceramics were prepared by low temperature sintering using traditional ceramic method. The influences of mixed mode, PZT shell and composition on structure, magnetic and magnetoelectric coupling properties were studied. XRD and TEM results show that CoFe₂O₄/PZT core-shell nanostructured particles are prepared by the Sol-Gel method. A 10-20 nm thick PZT shell formed on the surface of CoFe₂O₄ particle. EDS analyses show that low temperature sintering and barrier layer effectively inhibit the elements diffusion of the two phases. SEM images and magnetoelectric property measurement show that PZT shell coated on CoFe₂O₄ particles and the stirring process improve the magnetic particles content in com-position, match the sintering process perfectly, and improve the magnetoelectric coupling properties effectively. The coated and stirred sample CoFe₂O₄-(PZN-PZT) with volume ratio of 4:6 which sintered at 1000℃ show maximum magnetoelectric coupling coefficient of (18.3 mV/(cm·Oe)) at 10 kHz.