(KxNa1-x)NbO3基陶瓷的热稳定性研究

Piezoelectric thermal stability in (KxNa1-x)NbO3 based Ceramics

摘要:

采用传统固溶反应法制备了(KxNa1?x)1-yLiyNb0.80Ta0.20O3 ( x=0.40–0.60 when y=0.030, 0.035, 0.040 ) 系列无铅压电陶瓷，研究了其压电性能的温度稳定性。实验得出在研究的组分范围内，陶瓷的压电常数d33可达到250 pC/N，kp到达50%。在高达约325oC的老化试验中发现，尽管在室温下存在多型相变的影响，但陶瓷的d33和kp值几乎一直保持不变。而且，陶瓷的kp值在-50癈到120癈这个很宽的温度范围内几乎不受温度影响，显示了很好的温度稳定性，笔者从两相共存的温度范围对陶瓷的热稳定性能进行了讨论。

Abstract:

Lead-free piezoelectric ceramics (KxNa1?x)1-yLiyNb0.80Ta0.20O3 ( x=0.40–0.60 when y=0.030, 0.035, 0.040 ) were prepared by conventional solid-state reaction method to investigate the thermal stability of piezoelectric properties. It has been found that samples in the researched compositional range have high piezoelectric constant of d33=250 pC/N and kp=50%, respectively. In the thermal aging test up to the Curie temperature of approximately 325oC, d33 and kp of the ceramics remain almost unchanged although there existing the polymorphic phase transition (PPT) near room temperature. Moreover, ceramics presents the very good piezoelectric temperature stability and kp show the weak temperature dependence over a wide measured temperature range from -50oC to 120oC. The excellent thermal stability was discussed from the aspect of temperature range of phase coexistance.