Spiral-shaped piezoelectric actuator fabricated using thermoplastic co-extrusion process

Spiral-shaped unimorph-type piezoelectric actuators were fabricated using a thermoplastic co-extrusion process. A green strip comprised of a piezoelectrically active layer (0.2PZN–0.8PZT) and a piezoelectrically passive layer (0.2PZN–0.8PZT/40 vol.% Ag) was produced by using the co-extrusion process. The green strip was then wound into a spiral shape at a temperature of 110 °C. After removing the thermoplastic binders, the samples were co-fired at 930 °C for 4 h in air. The fabricated actuator showed high displacements in the tangential direction due to its unimorph design and spiral geometry.