不同频率对埋入式压电陶瓷辐射声波的影响

不同频率激励埋入式压电陶瓷,辐射声波的声压、声强和指向性不同。为提高超声无损检测的精度,正确选用激励频率十分重要。通过ANSYS软件对埋入式压电陶瓷进行有限元分析,得到在20~100kHz频率范围内不同振动模态对应的固定频率,使用所得频率对压电陶瓷进行激励,分析不同频率激励压电陶瓷辐射超声波的影响,选定最佳固定频率。结果表明在20~100kHz频率范围内,共有14个振动模态,9个振动模态的振幅达到极值,声压随频率的增大逐渐增强,当频率达到79.666kHz时为最大值,而后逐渐衰减,且在67.301~84.895kHz频段内变化十分迅速。

The Influence of Different Frequency to the Acoustic Wave from the Embedded PZT Ceramic

Using different frequencies to stimulate the embedded piezoelectric ceramic,it will radiate different acoustic pressure,and produce various acoustic strength and acoustic directivity.In order to improve the accuracy of nondestructive testing about acoustic wave,it＇s important to choose the appropriate stimulated frequency.We use the software of ANSYS to analyze the piezoelectric ceramic,and find out the different inherent frequencies of corresponding vibration modal between 20kHz and 100kHz.Then using the frequencies found to inspire the piezoelectric ceramic to analyze the acoustic wave from the embedded PZT ceramic.The results show that there are 14 vibration modals,including 9 amplitudes which reach at the extremum.The acoustic pressure will increase gradually with the increasing frequency until 79.666kHz,and then it will weaken.Moreover,from 67.301kHz to 84.895kHz,the tendency variation is very fast.