压电陶瓷在激光干涉错位散斑检测中的一些应用

Some Applications of Piezoelectric Ceramic in Non-Contact Detection Using Laser Shearography

对检测表面或检测构件施加振动激励以达到探测构件表层下缺陷的目的。将压电陶瓷元件接入适当的电压调节控制电路,利用压电陶瓷的逆压电效应原理,通过计算机程序可以让压电陶瓷元件发生随电压变化的微位移,电压的变化由程序设定,按应用场合的不同,可分别使压电陶瓷的微位移变成检测所需要的相移或振动。多次的实际检测结果表明,在一些航空材料粘接构件的激光干涉无损检测(NDT)中,压电陶瓷是目前人们实现相移和振动激励等特殊功能的最佳选择之一。

Based on the principle of inverse piezoelectric effect, connecting piezoelectric ceramic shifter to an adjustable power source, the micro-displacement on the shifter surface takes place together with change of voltage adjusted by computer program. According to the different need, the micro-displacement could be changed into a phase-shift or a vibration. The testing results show that in the case of inspecting adhesion quality of aeronautical components piezoelectric ceramic is so far one of the best choices to make a phase shifter or vibration exciter .