Abstract:Piezoelectric actuators have been playing a very important role in modern industries. However, the current used PZT acutaors are based on linear piezoelectric effect, with the maximum output strain is only 0.1-0.15%. Realization of large strain is always the goal of scholars in this field. In this work, we proposed two types of PZT ring multilayer actuators based on reversible non-180 ° domain switching. One is the radially-poled, partially electroded (RPPE) 4-layer ring, the other is the periodically orthogonal poled (POP) 4-layer rings. Experimental results show that under the same driving field (2kV / mm, 0.1Hz), the maximum actuation strain of 4-layer RPPE actuator is 0.27%, about twice that of conventional PZT ring, but the surface deformation is not uniform. As to the 4-layer POP ring actuator, the maximum output strain is 0.36%, about 2.7 times strain of conventional PZT ring, and the deformation is very uniform over the surface. The actuation strain of both actuators decreases with the increasing driving frequency. The strain of the RPPE actuator was stabilized at 0.19% when the driving frequency exceeds 1Hz, and that of the POP actuator keeps at 0.2% when the driving frequency exceeds 5Hz. Furthermore, the actuation strain of the 4-layer POP ring actuator is very stable and keeps unchanged after 20k cycles of operation. The POP ring multi-layer actuator has the advantages of large output strain and stable configuration, and may get wide applications in the actuation field.