预压力对压电叠层作动器性能的影响

由于压电叠层作动器只能承受压力，为了保证压电智能主动杆能够承受一定的拉力，设计了预压装置。为了考察压电叠层作动器在受压情况下的工作性能，设计了压电叠层作动器的受压性能实验。实验结果表明，在一定的压力作用下，输出位移增加，迟滞度减小。分析认为，在压力作用下压电陶瓷晶体结构发生变化，对逆压电效应产生影响，在电场作用下导致输出位移增大和迟滞度减小。

Influence of Preload on the Properties for Piezoelectric Stack Actuator

As the piezoelectric stack actuator can withstand pressure only,a preload device is designed to ensure that the intelligent active member can experience tensile stress. In this paper,a preload experiment is carried out to test the influence of preload on actuator's properties. The results show that the output displacement increases and the hysteresis degree descrease under certain preload. The mechanism is that the crystal structure of the piezoelectric ceramic is changed by the preload and the converse piezoelectric effect is enhanced,leading to the above results when electric field is applied.