LARGE-DISPLACEMENT PZT PIEZOELECTRICS WITH COMPOSITE STRUCTURE

A new kind of large-displacement piezoelectric ceramics for actuators composed of reduced and un-reduced layers was prepared from PZT by chemical reduction. The distribution of stress inside the composite structure was researched and the chemical reduction conditions were explored. The actuating properties of reduced PZT were studied. It is found that the optimal ratio of reduced layer thickness for the composite structure is 0.3. The reduced composite PZT has lower resonance frequency and 3 times larger displacement than that of the traditional PZT. The re-oxide phases are found in the reduced layer of the composite PZT, showing that the reduction procedure needs to be improved.