Piezoelectric properties of the sandwich structured PZT ceramics

Abstract

Sandwich structured PZT/PZT composites piezoelectric ceramics consisting of two different Pb(Zr,Ti)O₃[PZT] compositions were uniformly sintered without any deformation or delamination at the joining layers of different compositions by changing the calcining temperatures of each composition to give the same shrinkage. The coupling factors, mechanical quality factors and resonant frequencies were almost linearly changed with the thickness ratio of constituent compositions. The piezoelectric constants, g₃₃ and d₃₃, agree well with the values calculated from equations proposed by Newnham for his addressed 2–2 connectivity composite. In the sandwich structured sample consisting of Pb(Zr_0.53Ti_0.47)O₃ and Pb(Zr_0.4Ti_0.6)O₃, the temperature coefficient of resonant frequency could be approached to almost zero at a volume ratio of 0.37/0.63.