改性PLZT陶瓷偏压压电效应的研究

Piezoelectric Effect Induced by DC Bias in PLZT Ceramics

本文讨论了铌和钡改性的PLZT 10 /6 5/35铁电陶瓷的横向场诱应变X2 ,不同温度及偏压下的介电常数K33,平面机电耦合系数kp 和弹性柔顺系数SE1 1 ,并计算了等效压电常数d31 。铌和钡改性的PLZT铁电陶瓷在 15kV/cm的电场下横向应变分别为 - 5.1× 10 - 4 和 - 4 .5× 10 - 4 。实验表明它们的kp和d31 值可由直流偏压控制 ,室温下kp 的饱和值分别为 0 .53和0 .52 ,|d31 |的最大值分别为 2 30pC/N和 2 2 5pC/N ,且压电常数的温度系数都比PMN -PT系陶瓷小得多。

Transverse field-induced strain X 2 ,electromechanical planar coupling factor k p,transverse elastic compliance S E 11 and dielectric constant K 33 under DC bias at different temperatures were measured for niobium and barium modified PLZT ceramics.The effective piezoelectric coefficient was calculated. The X 2 at 15kV/cm for Nb and Ba modified PLZT ceramics are -5.1×10 -4 and -4.5×10 -4 respectively.Experiments show k p and d 31 of PLZT ceramics are tunable.Maximums of k p and ｜d 31 ｜ under DC bias for the compositions are 0.53 and 0.52,230pC/N and 225pC/N respectively at room temperature.The value of d 31 of PLZT ceramics is much less temperature dependent compared to that of PMN-PT ceramics.