Quasi-static thermo-electro-mechanical behaviour of piezoelectric stack actuators

Quasi-static thermo-electro-mechanical performance of annular and solid cylindrical piezoelectric actuators was studied by experimental means under electric fields varying from 0.3 to 1.8 kV mm −1 with a preload of 4.6 MPa over the temperature range of −30 to 125 ◦ C. It was found that, for both annular and solid actuators, the electrically induced stroke increases steadily with temperature. Under electric fields larger than 1.0 kV mm −1 , a nonlinear transition zone exists in the stroke-temperature plot over the temperature range 25-50 ◦ C. The dielectric constant was also found to increase with temperature. Preload dependence of displacement was measured up to 42 MPa at room temperature and found to be negligible below 30 MPa. A mathematical model that includes the linear piezoelectric effect and 90 ◦ domain switching effect was used to model the experimental results. The model shows reasonable agreement with experimental results at low and high driving fields. (Some figures in this article are in colour only in the electronic version)