材料期刊网

采用传统固相法制备了掺镧锆钛酸铅(PLZT)铁电陶瓷,经不同方向极化后,进行了交变电场循环加载疲劳试验,原位测试了不同循环周次下的Raman谱和电滞回线,分析了Raman软模强度和剩余极化强度的变化规律.结果表明:此铁电陶瓷在交变电场作用下的畴变导致了Raman峰强度和铁电性能的下降;随循环周次的增加,Raman软模相对强度和相对剩余极化强度均先快速下降后再缓慢下降,且下降趋势由急变缓的拐点基本出现在循环106.2周次时;纵向极化试样的Raman谱软模相对强度和相对剩余极化强度随循环周次增加的下降幅度大于未极化和切向极化试样的.

Lanthanum-doped lead zirconate titanate (PLZT) ceramics were prepared by conventional solid state reaction technique and polarized in different directions.Then the cyclic loading fatigue experiment under an alternating electric field was conducted on the ceramics.The Raman spectra and hysteresis loops were in-situ measured at different cycles,and then the variations of Raman spectra intensity for soft modes and remanent polarization were analyzed.The results show that Raman spectra intensity and ferroelectricity of the ceramics decreased due to the domain switching produced during the fatigue process under the cyclic altemating electric field.With the increase of the cycles,the Raman relative intensity for soft modes and the relative intensity for remanent polarizationin decreased first rapidly then slowly with the same turning point at about 106.2 cycles.The Raman relative intensity for soft modes and the relative intensity for remanent polarizationin of the out-of-plane polarized specimen decreased with the largest reduction among those of non-polarized and in-plane polarized specimens,with the cycle increasing.