LiSbO3含量对BiMnO3掺杂K(0.5)Na(0.5)NbO3陶瓷的结构与压电性能的影响研究

Effect of LiSbO_3 Content on the Microstructure and Piezoelectric Properties of K_(0.5)Na_(0.5)NbO_3 Lead-free Ceramics Doped with BiMnO_3

采用传统陶瓷常压烧结工艺制备(0.996–x)KNN-0.004BM-xLS(x=0、0.01、0.02、0.03、0.04、0.05、0.06)无铅压电陶瓷,着重研究了LS的含量对(0.996–x)KNN-0.004BM-xLS陶瓷相结构和压电性能的影响。结果表明,当x≤0.02时,陶瓷具有单一的正交相结构;当0.03≤x≤0.05时,陶瓷具有正交相与四方相共存的过渡结构;当x=0.06时,陶瓷具有单一的四方相结构。陶瓷的MPB成分范围在0.03≤x≤0.05。随着LS含量的增加,陶瓷材料的d33和kp均先增加后减小,当x=0.05时,均达到最大值,分别为230 pC/N和0.42;陶瓷的To-t和Tc均向低温方向移动;当x=0时,陶瓷的To-t和Tc分别为455和215℃;当x=0.02时,陶瓷的To-t和Tc分别为385和150℃;当x=0.06时,To-t和Tc分别降至370℃和75℃。

Lead-free （0.996-x）KNN-0.004BM-xLS （x=0, 0.01, 0.02, 0.03, 0.04, 0.05, 0.06） ceramics were prepared by the traditional ceramic sintering processing. The effect of LS content on the microstructure and piezoelectric properties of KNN-BM lead-free ceramics was investigated. The results show that the ceramics have a single orthorhombic phase structure when x≤0.02, a co-existed phases orthorhombic and tetragonal phases structure at 0.03 ≤x≤0.05, and a single tetragonal phase structure at x=0.06. The morphotropic phase boundary （MPB） for the ceramics is identified in the composition range of 0.03≤x≤0.05. With increasing the LS content, both d33 and kp of the ceramics firstly increase and then decrease. At x=0.05, d33 and kp reach their maximum values which are 230 pC/N and 0.42, respectively. The To-t and Tc of the ceramics shift to the low temperature with the increasing of the LS content. The To.t and Tc of the ceramics are 455 and 215℃ at x=0, 385 and 150℃ at x=0.02, 370 and 75℃ at x=0.06, respectively.