Study of RAINBOW Actuator and its Intergation with SMA

A new kind of large-displacement piezoelectric actuator — reduced and internally biased oxide wafer (RAINBOW) actuator composed of reduced and unreduced layers, is prepared from PZT (Pb(Zr _x Ti _1-x )O ₃ ) by chemical reduction. Its phase components, microstructure, and actuating properties are also researched. It is found that the displacement of reduced RAINBOW PZT is three times larger than that of the traditional PZT; however, re-oxide phases are found in the reduced layer of composite PZT, showing that the reduction procedure needs to be improved. Furthermore, the possibility of the integration between PZT and shape memory alloy (SMA) is explored. Physical vapor deposition (PVD) method is applied to depose SMA films on the reduced layer of RAINBOW PZT patches. Results of mechanical and actuating experiments show that this kind of integration is a reasonable idea to manufacture actuators with better performance.