(1.厦门工学院机械与材料工程学院，厦门 361021；
2. 厦门大学材料学院，厦门 361005；
3. 厦门大学福建省特种先进材料重点实验室，厦门 361005)
摘 要: 利用原位XRD技术研究未极化掺镧锆钛酸铅(PLZT)铁电陶瓷在不同直流电场加载过程中(002)和(200)衍射峰峰强与电场强度的关系，基于铁电畴取向分布的考虑，对(002)和(200)衍射峰峰强进行定量分析。通过对原位XRD谱进行四方相和单斜相的分峰拟合处理，初步探讨电场强度对铁电陶瓷电致畴变和电致相变的影响。结果表明：对于PLZT试样，在电场加载过程中除了发生电致90°畴变外，还可能发生从四方相到单斜相的电致相变。在不同电场强度作用下，电致畴变与电致相变是一个相互竞争的过程，电致畴变是主要的，而电致相变相对减少。
关键字: 铁电陶瓷；原位XRD；电致畴变；相变
（1. College of Mechanical and Materials Engineering, Xiamen Institute of Technology, Xiamen 361021, China;
2. College of Materials, Xiamen University, Xiamen 361005, China;
3.Fujian Key Laboratory of Advanced Materials, Xiamen University, Xiamen 361005, China）
Abstract:Variations of the peak intensities of (002) and (200) diffraction peaks (I(002), I(200)) with the applied electric fields were studied by in-situ X-ray diffraction method during the applications of different electric fields on the unpoled lanthanum-doped lead zirconate titanate (PLZT) ceramics. Considering the distribution of domain orientation, the quantitative analyses of peak intensities of I(002) and I(200) were performed. Based on the multi-peak curve fitting to the in-situ XRD spectra, the effects of the applied electric fields on the electric-field-induced domain switching and phase transition were preliminarily discussed. The results show that the electric-field-induced 90° domain switching occurs in PLZT specimens under the applied electric fields, at the same time, the electric-field-induced phase transition from tetragonal to monoclinic could also happen. The electric-field-induced domain switching and phase transition occur competitively in different electric fields. The major process is domain switching, while the minor process is phase transition.
Key words: ferroelectric ceramics; in-situ XRD; electric-field-induced domain switching; phase transition
